Thanks Boris!

This looks very reasonable to me, but I might not be the right person to review it, as I don't know much about front end stuff. Looking at https://mui.com/api/form-label/ I see that false is the default here, so I'm curious why it gets a different value when not specified, but mostly out of curiosity, because I too experience that when the window goes in and out of focus, the rendering changes (e.g. alt-tabbing between firefox and a different app) after a checkbox has been selected. Can you confirm that after selecting a checkbox, the rendering no longer changes when moving the focus to a different application? On mine, when I have firefox window in focus, the text is faint and unreadable, but if I move focus to a different app (e.g. Zoom) the text becomes readable again, and then moving focus back to firefox, is fades again (so is only readable when the window is not in focus).

The above CI failure is completely unrelated to this change, but is rather concerning:

[task 2022-01-21T16:17:06.186Z] Installing collected packages: taskgraph
[task 2022-01-21T16:17:06.187Z]   Running setup.py install for taskgraph: started
[task 2022-01-21T16:17:06.467Z]     Running setup.py install for taskgraph: finished with status 'done'
[task 2022-01-21T16:17:06.485Z] Successfully installed taskgraph-0.0.1
[task 2022-01-21T16:17:06.515Z] + PIP_IGNORE_INSTALLED=0
[task 2022-01-21T16:17:06.515Z] + pip install --user arrow taskcluster pyyaml
[task 2022-01-21T16:17:07.093Z] Collecting arrow
[task 2022-01-21T16:17:07.316Z]   Downloading https://files.pythonhosted.org/packages/ca/bc/ebc1afb3c54377e128a01024c006f983d03ee124bc52392b78ba98c421b8/arrow-0.17.0-py2.py3-none-any.whl (50kB)
[task 2022-01-21T16:17:07.352Z] Collecting taskcluster
[task 2022-01-21T16:17:07.526Z]   Downloading https://files.pythonhosted.org/packages/c5/86/b971767fae850e3d6daa894e3f429e31f459a2159bb07e97537de28fa8e1/taskcluster-44.4.0.tar.gz (106kB)
[task 2022-01-21T16:17:07.757Z]     Complete output from command python setup.py egg_info:
[task 2022-01-21T16:17:07.757Z]     Traceback (most recent call last):
[task 2022-01-21T16:17:07.757Z]       File "<string>", line 1, in <module>
[task 2022-01-21T16:17:07.757Z]       File "/tmp/pip-build-S832Dc/taskcluster/setup.py", line 64, in <module>
[task 2022-01-21T16:17:07.757Z]         with open('README.md', encoding='utf8') as f:
[task 2022-01-21T16:17:07.757Z]     TypeError: 'encoding' is an invalid keyword argument for this function
[task 2022-01-21T16:17:07.757Z]     
[task 2022-01-21T16:17:07.757Z]     ----------------------------------------

We removed support for python 2 in release 44.4.0, and it looks like something depends on it that we didn't catch. :-(

@petemoore

Looking at https://mui.com/api/form-label/ I see that false is the default here, so I'm curious why it gets a different value when not specified...

It seems like the FormGroup component sets this focused prop for some reason. You can see their example behaves identically to ours, except for the fact that our label becomes unreadable. I'm not too sure why this is, but I decided to just try hardcoding it to false, and that's what worked.

Can you confirm that after selecting a checkbox, the rendering no longer changes when moving the focus to a different application?

Yep! Label does not change at all with this fix implemented. You can also get the style back to "readable" if you click somewhere else on the page, like the label text, for example.

The above CI failure is completely unrelated to this change, but is rather concerning:

[task 2022-01-21T16:17:06.186Z] Installing collected packages: taskgraph
[task 2022-01-21T16:17:06.187Z]   Running setup.py install for taskgraph: started
[task 2022-01-21T16:17:06.467Z]     Running setup.py install for taskgraph: finished with status 'done'
[task 2022-01-21T16:17:06.485Z] Successfully installed taskgraph-0.0.1
[task 2022-01-21T16:17:06.515Z] + PIP_IGNORE_INSTALLED=0
[task 2022-01-21T16:17:06.515Z] + pip install --user arrow taskcluster pyyaml
[task 2022-01-21T16:17:07.093Z] Collecting arrow
[task 2022-01-21T16:17:07.316Z]   Downloading https://files.pythonhosted.org/packages/ca/bc/ebc1afb3c54377e128a01024c006f983d03ee124bc52392b78ba98c421b8/arrow-0.17.0-py2.py3-none-any.whl (50kB)
[task 2022-01-21T16:17:07.352Z] Collecting taskcluster
[task 2022-01-21T16:17:07.526Z]   Downloading https://files.pythonhosted.org/packages/c5/86/b971767fae850e3d6daa894e3f429e31f459a2159bb07e97537de28fa8e1/taskcluster-44.4.0.tar.gz (106kB)
[task 2022-01-21T16:17:07.757Z]     Complete output from command python setup.py egg_info:
[task 2022-01-21T16:17:07.757Z]     Traceback (most recent call last):
[task 2022-01-21T16:17:07.757Z]       File "<string>", line 1, in <module>
[task 2022-01-21T16:17:07.757Z]       File "/tmp/pip-build-S832Dc/taskcluster/setup.py", line 64, in <module>
[task 2022-01-21T16:17:07.757Z]         with open('README.md', encoding='utf8') as f:
[task 2022-01-21T16:17:07.757Z]     TypeError: 'encoding' is an invalid keyword argument for this function
[task 2022-01-21T16:17:07.757Z]     
[task 2022-01-21T16:17:07.757Z]     ----------------------------------------

John is working on a fix for this in #5071.