Maybe you can explain the problem in more detail.

Is this about Firefox updating? The Firefox distro version that you use in managed by your Linux OS software management.

You can consider Firefox from the official Mozilla server if you currently use a version from the repositories of your Linux distribution to see if it behaves differently.

• https://www.mozilla.org/en-US/firefox/all/#product-desktop-release

"Check for updates but let you choose to install them" only delays updates, not stop them completely.

During normal use, nor during update, Firefox stops doing anything and gives an option to quit or wait, and then quits anyway after choosing wait several times.

During normal operation, Firefox puts up a box that says software is slowing it down with a option to quit whatever it is doing or wait. After choosing wait several times, it quits anyway.

Is this the bar with a message that a tab is slowing Firefox, or something along those lines? It indicates that a script in the page is non-responsive. It may be performing a long/slow operation and not need to be halted, or it could be frozen. However, a script crashing a tab shouldn't take down Firefox. In that case, there probably is a bug that needs fixed. Do you want to share some crash report IDs? More info on how best to do that here: Firefox crashes - asking for support.

In case of a tab crash, you usually do not get the option to submit a crash report, this makes it harder to investigate. You can check the Browser Console to see if there are messages about a tab crash.

• https://firefox-source-docs.mozilla.org/devtools-user/browser_console/

Does it still happen in Troubleshoot Mode?