Problem: Get Started and Apache Friends buttons not working on Xampp 8.1.10-0
I have fixed this problem for Debian 9 Stretch by using strace to see what was failing to launch.
Here is the significant code:-
Running Firefox as root in a regular user's session is not supported. ($XAUTHORITY is /home/john/.Xauthority which is owned by john.)
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: seamonkey: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: mozilla: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: epiphany: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: konqueror: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: chromium-browser: not found
[2379:2379:1206/154132.708079:ERROR:zygote_host_impl_linux.cc(90)] Running as root without --no-sandbox is not supported. See https://crbug.com/638180.
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: www-browser: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: links2: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: elinks: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: links: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: lynx: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: w3m: not found
xdg-open: no method available for opening 'http://wiki.bitnami.com/Infrastructure_Stacks/BitNami_for_XAMPP'
The problem is that from Debian 9 Stretch Firefox cannot be run as root but Xampp needs root privelege to start owing to Apache. If you look at the quoted code you can see that many other browsers are tried in the starting sequence on pressing Get Started so I began by installing Seamonkey in /usr/lib/ to see if it would work. I made a soft link (ln -s) from /usr/bin/ and also an entry in /usr/share/applications/ for the menu (followed by apt-get update to activate).
The result is that on clicking the Get Started button and the Apache Friends button on the Xampp control panel, Seamonkey launches with superuser priveleges and opens the relevant pages.