[🐛 Bug]: Message: binary is not a Firefox executable

[arghorashy]

Description

I have a python script I have working on one computer, but when I try to run it on my server I get the following error:

    self.driver = webdriver.Firefox(service=service, options=options)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/firefox/webdriver.py", line 71, in __init__
    super().__init__(command_executor=executor, options=options)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 241, in __init__
    self.start_session(capabilities)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 329, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 384, in execute
    self.error_handler.check_response(response)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/errorhandler.py", line 232, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.InvalidArgumentException: Message: binary is not a Firefox executable

Here is the code I'm running:

from selenium import webdriver
from selenium.webdriver.firefox.options import Options
from selenium.webdriver.firefox.firefox_binary import FirefoxBinary
import selenium.webdriver.firefox.service as FirefoxService

options = Options()
service = FirefoxService.Service(executable_path='/snap/bin/geckodriver')
options.binary_location = "/usr/bin/firefox"
webdriver.Firefox(service=service, options=options)

On my computer where this worked, I didn't need to specify locations for geckodriver or firefox. If I get rid of the arguments to webdriver.Firefox, I get the same result, by the way, so I'm not sure they're doing anything...

Here is some relevant version info for the original computer where this worked:

• OS: Linux Mint 22.1
• Python v3.12.3
• Selenium v4.27.1
• Firefox v135.0.1
• Gecko - interestingly which geckodriver returns nothing

Here is some version information for the server where I am encountering this issue:

• OS: Ubuntu 22.04.5 LTS
• Python v3.12.10
• Selenium v4.31.0
• Firefox v138.0
• Gecko v0.36.0

Reproducible Code

from selenium import webdriver
from selenium.webdriver.firefox.options import Options
from selenium.webdriver.firefox.firefox_binary import FirefoxBinary
import selenium.webdriver.firefox.service as FirefoxService

options = Options()
service = FirefoxService.Service(executable_path='/snap/bin/geckodriver')
options.binary_location = "/usr/bin/firefox"
webdriver.Firefox(service=service, options=options)

Debugging Logs

self.driver = webdriver.Firefox(service=service, options=options)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/firefox/webdriver.py", line 71, in __init__
    super().__init__(command_executor=executor, options=options)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 241, in __init__
    self.start_session(capabilities)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 329, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 384, in execute
    self.error_handler.check_response(response)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/errorhandler.py", line 232, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.InvalidArgumentException: Message: binary is not a Firefox executable

[selenium-ci]

@arghorashy, thank you for creating this issue. We will troubleshoot it as soon as we can.

Selenium Triage Team: remember to follow the Triage Guide

[cgoldberg]

It looks like you are running the Snap version of geckodriver, but a non-Snap version of Firefox? That might be problematic.

If I get rid of the arguments to webdriver.Firefox, I get the same result

That should work (it will download the latest Firefox and geckodriver)

Can you please do the following:

• enable DEBUG level logging: https://www.selenium.dev/documentation/webdriver/troubleshooting/logging/
• Try again using webdriver.Firefox() with no args
• paste the log output here

[arghorashy]

Thanks for your reply. Per your instructions, I ran this:

import logging
logger = logging.getLogger('selenium')
logger.setLevel(logging.DEBUG)
log_path = './log'
handler = logging.FileHandler(log_path)
logger.addHandler(handler)

from selenium import webdriver
webdriver.Firefox()

In STDOUT I got this:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/firefox/webdriver.py", line 71, in __init__
    super().__init__(command_executor=executor, options=options)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 250, in __init__
    self.start_session(capabilities)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 342, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 429, in execute
    self.error_handler.check_response(response)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/errorhandler.py", line 232, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.InvalidArgumentException: Message: binary is not a Firefox executable

In my log file I got this output:

Selenium Manager binary found at: .venv/lib/python3.12/site-packages/selenium/webdriver/common/linux/selenium-manager
Executing process: .venv/lib/python3.12/site-packages/selenium/webdriver/common/linux/selenium-manager --browser firefox --debug --language-binding python --output json
Found geckodriver 0.36.0 in PATH: /snap/bin/geckodriver
firefox detected at /usr/bin/firefox
Running command: /usr/bin/firefox -v
Output: "Mozilla Firefox 138.0"
Detected browser: firefox 138.0
Required driver: geckodriver 0.36.0
Driver path: /snap/bin/geckodriver
Browser path: /usr/bin/firefox
Started executable: `/snap/bin/geckodriver` in a child process with pid: 5691 using 0 to output -3
POST http://localhost:55333/session {'capabilities': {'firstMatch': [{}], 'alwaysMatch': {'browserName': 'firefox', 'acceptInsecureCerts': True, 'moz:debuggerAddress': True, 'pageLoadStrategy': <PageLoadStrategy.normal: 'normal'>, 'browserVersion': None, 'moz:firefoxOptions': {'binary': '/usr/bin/firefox', 'prefs': {'remote.active-protocols': 3}}}}}
Remote response: status=400 | data={"value":{"error":"invalid argument","message":"binary is not a Firefox executable","stacktrace":""}} | headers=HTTPHeaderDict({'content-type': 'application/json; charset=utf-8', 'cache-control': 'no-cache', 'content-length': '101', 'date': 'Wed, 30 Apr 2025 20:59:32 GMT'})
Finished Request

[selenium-ci]

We need more information about this issue in order to troubleshoot.

Please turn on logging and re-run your code. Information on how to adjust logs for your language can be found in our
Troubleshooting documentation.

[cgoldberg]

@arghorashy
The log shows it is still using your system browser/driver rather than downloading the latest. I'm not sure why that is happening.

Can you try running your code with the SE_FORCE_BROWSER_DOWNLOAD environment variables set to true? So in your shell, just run export SE_FORCE_BROWSER_DOWNLOAD=true, then run your code.

@bonigarcia Do you know what is going on here? Based on the code/log shown in #15683 (comment) , shouldn't Selenium Manager not be using the system driver/browser?

[titusfortner]

If the user has the location of a driver in the PATH environment variable, that driver will be used.

That code is telling Selenium to use the snap driver with a non-snap installation of firefox.
The snap driver is different from the driver you download, so remove its location from PATH if you don't want to use it.

[arghorashy]

Someone mentioned that using a non-Snap version of Firefox and a Snap version of geckodriver was part of the problem, so I ran sudo apt remove firefox, as I had only installed it in an attempt to get this to work. To check Firefox was gone, I executed which firefox, expecting it to return nothing, but to my surprise, it returned /snap/bin/firefox. I double-checked which geckodriver, which returned /snap/bin/geckodriver. I assumed this meant they were both from Snap, so I figured things might now work based on the comment about mixing non-Snap and Snap...

I ran this:

import logging
logger = logging.getLogger('selenium')
logger.setLevel(logging.DEBUG)
log_path = './log'
handler = logging.FileHandler(log_path)
logger.addHandler(handler)

from selenium import webdriver
webdriver.Firefox()

I got this in STDOUT (not the original "binary is not a Firefox executable" message):

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/firefox/webdriver.py", line 71, in __init__
    super().__init__(command_executor=executor, options=options)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 250, in __init__
    self.start_session(capabilities)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 342, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 429, in execute
    self.error_handler.check_response(response)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/errorhandler.py", line 232, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.WebDriverException: Message: Process unexpectedly closed with status 1

I got this in the log file (500 error):

Selenium Manager binary found at: .venv/lib/python3.12/site-packages/selenium/webdriver/common/linux/selenium-manager
Executing process: .venv/lib/python3.12/site-packages/selenium/webdriver/common/linux/selenium-manager --browser firefox --debug --language-binding python --output json
Found geckodriver 0.36.0 in PATH: /snap/bin/geckodriver
Found firefox in PATH: /snap/bin/firefox
Using firefox snap: /snap/firefox/current/usr/lib/firefox/firefox
Running command: /snap/firefox/current/usr/lib/firefox/firefox -v
Output: "Mozilla Firefox 138.0"
Detected browser: firefox 138.0
Required driver: geckodriver 0.36.0
Driver path: /snap/bin/geckodriver
Browser path: /snap/firefox/current/usr/lib/firefox/firefox
Started executable: `/snap/bin/geckodriver` in a child process with pid: 7454 using 0 to output -3
POST http://localhost:51705/session {'capabilities': {'firstMatch': [{}], 'alwaysMatch': {'browserName': 'firefox', 'acceptInsecureCerts': True, 'moz:debuggerAddress': True, 'pageLoadStrategy': <PageLoadStrategy.normal: 'normal'>, 'browserVersion': None, 'moz:firefoxOptions': {'binary': '/snap/firefox/current/usr/lib/firefox/firefox', 'prefs': {'remote.active-protocols': 3}}}}}
Remote response: status=500 | data={"value":{"error":"unknown error","message":"Process unexpectedly closed with status 1","stacktrace":""}} | headers=HTTPHeaderDict({'content-type': 'application/json; charset=utf-8', 'cache-control': 'no-cache', 'content-length': '105', 'date': 'Thu, 01 May 2025 00:56:58 GMT'})
Finished Request

I then tried running export SE_FORCE_BROWSER_DOWNLOAD=true and then running the same set of python commands again. Here is what I got in STDOUT (back to the "binary is not a Firefox executable" mesage):

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/firefox/webdriver.py", line 71, in __init__
    super().__init__(command_executor=executor, options=options)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 250, in __init__
    self.start_session(capabilities)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 342, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 429, in execute
    self.error_handler.check_response(response)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/errorhandler.py", line 232, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.InvalidArgumentException: Message: binary is not a Firefox executable

This is what I got in the log file (400 error):

Selenium Manager binary found at: .venv/lib/python3.12/site-packages/selenium/webdriver/common/linux/selenium-manager
Executing process: .venv/lib/python3.12/site-packages/selenium/webdriver/common/linux/selenium-manager --browser firefox --debug --language-binding python --output json
Found geckodriver 0.36.0 in PATH: /snap/bin/geckodriver
Required browser: firefox 138.0
firefox 138.0 already exists
firefox 138.0 is available at /home/arg/.cache/selenium/firefox/linux64/138.0/firefox
Required driver: geckodriver 0.36.0
Driver path: /snap/bin/geckodriver
Browser path: /home/arg/.cache/selenium/firefox/linux64/138.0/firefox
Started executable: `/snap/bin/geckodriver` in a child process with pid: 7788 using 0 to output -3
POST http://localhost:60397/session {'capabilities': {'firstMatch': [{}], 'alwaysMatch': {'browserName': 'firefox', 'acceptInsecureCerts': True, 'moz:debuggerAddress': True, 'pageLoadStrategy': <PageLoadStrategy.normal: 'normal'>, 'browserVersion': None, 'moz:firefoxOptions': {'binary': '/home/arg/.cache/selenium/firefox/linux64/138.0/firefox', 'prefs': {'remote.active-protocols': 3}}}}}
Remote response: status=400 | data={"value":{"error":"invalid argument","message":"binary is not a Firefox executable","stacktrace":""}} | headers=HTTPHeaderDict({'content-type': 'application/json; charset=utf-8', 'cache-control': 'no-cache', 'content-length': '101', 'date': 'Thu, 01 May 2025 01:00:33 GMT'})
Finished Request

Finally, I decided to pull out the big guns and run sudo snap remove firefox and even for good measure, sudo snap remove geckodriver. I verified both were gone using which commands.

I ran the same python commands with the environment variable still set. Here is what I got on the console:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/firefox/webdriver.py", line 71, in __init__
    super().__init__(command_executor=executor, options=options)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 250, in __init__
    self.start_session(capabilities)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 342, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 429, in execute
    self.error_handler.check_response(response)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/errorhandler.py", line 232, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.WebDriverException: Message: Process unexpectedly closed with status 1

Here is what I got in the log file:

Selenium Manager binary found at: .venv/lib/python3.12/site-packages/selenium/webdriver/common/linux/selenium-manager
Executing process: .venv/lib/python3.12/site-packages/selenium/webdriver/common/linux/selenium-manager --browser firefox --debug --language-binding python --output json
geckodriver not found in PATH
Required browser: firefox 138.0
firefox 138.0 already exists
firefox 138.0 is available at /home/arg/.cache/selenium/firefox/linux64/138.0/firefox
Required driver: geckodriver 0.36.0
Acquiring lock: /home/arg/.cache/selenium/geckodriver/linux64/0.36.0/sm.lock
Downloading geckodriver 0.36.0 from https://github.com/mozilla/geckodriver/releases/download/v0.36.0/geckodriver-v0.36.0-linux64.tar.gz
Driver path: /home/arg/.cache/selenium/geckodriver/linux64/0.36.0/geckodriver
Browser path: /home/arg/.cache/selenium/firefox/linux64/138.0/firefox
Started executable: `/home/arg/.cache/selenium/geckodriver/linux64/0.36.0/geckodriver` in a child process with pid: 10572 using 0 to output -3
POST http://localhost:53541/session {'capabilities': {'firstMatch': [{}], 'alwaysMatch': {'browserName': 'firefox', 'acceptInsecureCerts': True, 'moz:debuggerAddress': True, 'pageLoadStrategy': <PageLoadStrategy.normal: 'normal'>, 'browserVersion': None, 'moz:firefoxOptions': {'binary': '/home/arg/.cache/selenium/firefox/linux64/138.0/firefox', 'prefs': {'remote.active-protocols': 3}}}}}
Remote response: status=500 | data={"value":{"error":"unknown error","message":"Process unexpectedly closed with status 1","stacktrace":""}} | headers=HTTPHeaderDict({'content-type': 'application/json; charset=utf-8', 'cache-control': 'no-cache', 'content-length': '105', 'date': 'Thu, 01 May 2025 01:07:29 GMT'})
Finished Request

Thanks for your help so far.

[cgoldberg]

The log looks like it downloaded Firefox and geckodriver (progress!), but Firefox didn't start.

Can you verify you are able to run Firefox without Selenium?

• run: /home/arg/.cache/selenium/firefox/linux64/138.0/firefox

Verify geckodriver can start also:

• run /home/arg/.cache/selenium/firefox/linux64/138.0/firefox

[bonigarcia]

The error binary is not a Firefox executable happened when Firefox was installed using SNAP. Selenium Manager supports Firefox SNAP browser/drivers as of version 0.4.30 (i.e., Selenium 4.3.x). So in theory, nothing needs to be done starting in that version.

[arghorashy]

@bonigarcia - In the first post I made, I got the binary is not a Firefox executable even when my Firefox install was in /usr/bin/firefox because I'd gotten it from apt, rather than Snap, so I believe the cause of getting this message is not that clear cut...? Of course, I could be wrong.

I ran firefox from the .cache folder (/home/arg/.cache/selenium/firefox/linux64/138.0/firefox) and it crashed with this message: Error: no DISPLAY environment variable specified

That's fair as this is a server, so I ran it gain with the -headless flag and it outputs this without returning unless I ctrl+c which makes me think it's working:

*** You are running in headless mode.
[GFX1-]: glxtest: Unable to open a connection to the X server
[GFX1-]: RenderCompositorSWGL failed mapping default framebuffer, no dt

I ran geckodriver from the .cache folder (/home/arg/.cache/selenium/geckodriver/linux64/0.36.0/geckodriver) and it hangs with this output which also seems like a good sign: 1746105993302 geckodriver INFO Listening on 127.0.0.1:4444

[cgoldberg]

@arghorashy So it looks like geckodriver starts fine, but Firefox can't... So your issue isn't related to Selenium.

I'm not sure why Firefox requires X11/Wayland in headless mode, but you might need to install one of those on your server. Once you can get Firefox to launch, Selenium should work fine.

[arghorashy]

I ran sudo apt install xauth xorg openbox and then ssh'd back into my machine with the -X flag and ran /home/arg/.cache/selenium/firefox/linux64/138.0/firefox and didn't get any of the GFX1 errors.

I then went run the python code I've been running over and over again and a Firefox browser opened!

It's at this point that I realized that I was running the wrong python code for this test! I'd forgotten the headless option. Here is the amended python code:

import logging
logger = logging.getLogger('selenium')
logger.setLevel(logging.DEBUG)
log_path = './log'
handler = logging.FileHandler(log_path)
logger.addHandler(handler)

from selenium import webdriver
from selenium.webdriver.firefox.options import Options
options = Options()
options.add_argument('--headless')
webdriver.Firefox(options)

I logged out and logged back in without the -X switch and ran this code and everything works.

So it looks like geckodriver starts fine, but Firefox can't...

So this wasn't quite right. When I ran firefox -headless, the GFX1 errors are not saying that Firefox is not working. The problem was that the separate test in python I was running was wrong and was trying to run Firefox in non-headless mode.

The Real Problem

I don't think all the errors I experienced can be attributed to this mistake though... I reinstalled Firefox (sudo apt install firefox, which firefox = /usr/bin/firefox) and re-ran the above code to get this in STDOUT:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/firefox/webdriver.py", line 71, in __init__
    super().__init__(command_executor=executor, options=options)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 250, in __init__
    self.start_session(capabilities)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 342, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 429, in execute
    self.error_handler.check_response(response)
  File ".venv/lib/python3.12/site-packages/selenium/webdriver/remote/errorhandler.py", line 232, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.InvalidArgumentException: Message: binary is not a Firefox executable

I get this in the log file:

Selenium Manager binary found at: .venv/lib/python3.12/site-packages/selenium/webdriver/common/linux/selenium-manager
Executing process: .venv/lib/python3.12/site-packages/selenium/webdriver/common/linux/selenium-manager --browser firefox --debug --language-binding python --output json
Found geckodriver 0.36.0 in PATH: /snap/bin/geckodriver
firefox detected at /usr/bin/firefox
Running command: /usr/bin/firefox -v
Output: "Mozilla Firefox 138.0"
Detected browser: firefox 138.0
Required driver: geckodriver 0.36.0
Driver path: /snap/bin/geckodriver
Browser path: /usr/bin/firefox
Started executable: `/snap/bin/geckodriver` in a child process with pid: 7207 using 0 to output -3
POST http://localhost:36443/session {'capabilities': {'firstMatch': [{}], 'alwaysMatch': {'browserName': 'firefox', 'acceptInsecureCerts': True, 'moz:debuggerAddress': True, 'pageLoadStrategy': <PageLoadStrategy.normal: 'normal'>, 'browserVersion': None, 'moz:firefoxOptions': {'binary': '/usr/bin/firefox', 'prefs': {'remote.active-protocols': 3}, 'args': ['--headless']}}}}
Remote response: status=400 | data={"value":{"error":"invalid argument","message":"binary is not a Firefox executable","stacktrace":""}} | headers=HTTPHeaderDict({'content-type': 'application/json; charset=utf-8', 'cache-control': 'no-cache', 'content-length': '101', 'date': 'Thu, 01 May 2025 14:15:49 GMT'})
Finished Request

I noticed that now I'm using /snap/bin/geckodriver and /usr/bin/firefox, which someone suggested might be a problem, so I ran sudo apt remove firefox and ran the test again and it worked! Checking the log file, I see that we're using /snap/bin/geckodriver and /snap/firefox/current/usr/lib/firefox/firefox. Both Snap! So it seems the fundamental roadblock I was experiencing was due to the fact that my geckodriver was from Snap, but Firefox was not.

I wonder if the error message should be made more clear? At least for my system, when I install firefox via apt, I end up with this mixed /snap/bin/geckodriver + /usr/bin/firefox which seems to be fatal!

[cgoldberg]

If it was me, I would steer clear of using Snap packaged Firefox and geckodriver and just let Selenium Manager deal with it.

[titusfortner]

Remove the snap directory from PATH environment variable
Selenium manager will use any driver found in a directory listed in that environment variable

Your code is still using the snap driver with a non snap browser

[arghorashy]

Your code is still using the snap driver with a non snap browser

Even though the log file cites these two paths?

/snap/bin/geckodriver
/snap/firefox/current/usr/lib/firefox/firefox

Seems like both are from Snap to me...

[titusfortner]

Look at the log file you pasted above. Selenium manager controls the browser location and this is what it is saying it is using:

Driver path: /snap/bin/geckodriver
Browser path: /usr/bin/firefox

[arghorashy]

Sorry for the confusion, but if you read the end of my post carefully, you'll see that that log file you are quoting is from the run where I reinstalled Firefox (sudo apt install firefox) and where my geckodriver was from snap but my Firefox was not.

Because my post was getting long, I did not post the log file for the final run I tried after running sudo apt remove firefox. Instead, I just posted the paths of geckodriver / firefox as they appeared in the log file.

Checking the log file, I see that we're using /snap/bin/geckodriver and /snap/firefox/current/usr/lib/firefox/firefox. Both Snap! So it seems the fundamental roadblock I was experiencing was due to the fact that my geckodriver was from Snap, but Firefox was not.

Just wanted to make sure that it was clear that I didn't need to abandon snap entirely to get my problems to go away. Rather, I just had to ensure I wasn't mismatching snap and non-snap...

Of course, I do take your point that it still might be best to just forgo snap altogether.