Currently, if you click the "Don't show this message again" checkbox and then select "Make Primary Browser", we intentionally don't respect the checkbox's value. It was confirmed in Bug 1134105 that this is the expected behavior.

Frankly, I'm not happy with the fact that we are apparently unwilling to accept that the user doesn't want to be alerted about this. Especially since our check for whether Firefox is already the default browser is, apparently, buggy (ex: Bug 1772662).

Regardless, if we are unwilling to give the user that option, we should at least be upfront about it, instead of giving them an option that simply does not work.

The current behavior was introduced with bug 1041516 when the text showed "Always perform this check when starting Firefox" but the checkbox behavior was flipped with bug 1701998 showing the string from bug 1705795 "Don't show this message again"

We probably want to figure out a better way to keep reminding users that Firefox is no longer the default to avoid permanently losing these users, but as the text is now, the behavior is quite misleading wanting some fix.

Perhaps it would be better if we just had 3 buttons? "Make Primary Browser", "Not now", "No, don't show this message again"?

I'd be happy to do that instead of my current patch.

Akash brought this up with James, and it sounds like we have the green light to change the behavior to always honor the user's checkbox choice as in your current patch. This avoids changing the designs/strings, and we can revisit later if necessary.

https://hg.mozilla.org/mozilla-central/rev/b6ed2f1c7ece

I managed to reproduce this issue on Firefox 102.0(build ID: 20220623063721) on Windows 10 64-bits; verified as fixed on Firefox 103.0b7(build ID: 20220710185935) and Nightly 104.0a1(build ID: 20220710190527) on Windows 10 64-bits, macOS 12 and Ubuntu 22.04.