Created attachment 148106 [details]
"postin" of file which does these things (extracted from microsoft-edge-stable-100.0.1185.39-1.x86_64.rpm with mc)

SUMMARY
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STEPS TO REPRODUCE
1. Install latest Microsoft Edge Browser (stable) from official RPM
2. Launch any link, e.g. via right clicking URL at Terminal
3. 

OBSERVED RESULT

Microsoft Edge opens

EXPECTED RESULT

System's previously setup default browser (Firefox in my case) should open

SOFTWARE/OS VERSIONS
Operating System: openSUSE Tumbleweed 20220409
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.2
Kernel Version: 5.17.1-1-default (64-bit)
Graphics Platform: X11
Processors: 2 × Intel® Core™2 Duo CPU P7350 @ 2.00GHz
Memory: 3.6 GiB of RAM
Graphics Processor: llvmpipe 

ADDITIONAL INFORMATION

As a user of Linux for decades, this is the first time I have seen update-alternatives (ab)used this way. I think time has come to prompt user if he/she really wanted to change default browser just like MacOS does. I don't suggest anything similar to Windows 11. Just a popup triggered by watching a file idle way would be enough.

Here is the relevant lines from RPM postin file:
 CHANNEL=stable
case $CHANNEL in
  stable )
    PRIORITY=200
    ;;
  beta )
    PRIORITY=150
    ;;
  unstable )
    PRIORITY=120
    ;;
  * )
    PRIORITY=0
    ;;
esac
 
/usr/sbin/update-alternatives --install /usr/bin/microsoft-edge \
  microsoft-edge /usr/bin/microsoft-edge-stable $PRIORITY
 
exit 0