Most apps crash instantly after hackjob

Ask Fedora
,
1

After breaking my Fedora 36 OS while retaining all files, I

  1. reinstalled Fedora with an account named after my old account
  2. dnf update
  3. rsynced new home folder to old home folder
  4. mounted old home folder as new home folder
  5. dnf update

And now some apps (Firefox, Brave, Vivaldi, Steam, sometimes Problem Reporting) will crash instantly, leaving either no descriptive text in Problem Reporting or merely

The backtrace does not contain enough meaningful function frames to be reported. It is annoying but it does not necessarily indicate a problem with your computer. ABRT will not allow you to create a report in a bug tracking system but you can contact kernel maintainers via e-mail.

Chromium works for some reason. And I did get one meaningful report, though:

A kernel problem occurred, but your kernel has been tainted (flags:GWI). Explanation:
W - Taint on warning.
I - Working around severe firmware bug.
Kernel maintainers are unable to diagnose tainted reports.

I’ve also tried reinstalling everything with yum reinstall \* and giving every user read and execute access everywhere. I couldn’t access some folders in /proc/ though, as well as /run/user/1000/doc/.

2

Step 3 and 4 (quoted) seem to be the issue.
Some config files (specific to certain apps) [mostly the dot files/directories] in your old home directory probably are not compatible with the newly updated apps that are causing issues.

This kind of hammer can totally break a system and should never be done. Unless you have a list of all files/directories where permissions were changed it is almost certain that the recovery will require a full system reinstall.