doesn't work on Waterfox and Librewolf browsers

[Polisson]

On those two browsers (Waterfox G4.1.1 and LibreWolf 99.0-1 - both 64bit) 100% reproducible is getting error window with such content:

Unable to launch browser, sorry :(

Please send a copy of this error to DanTup.

System.ComponentModel.Win32Exception (0x80004005): Nie można odnaleźć określonego pliku
   w System.Diagnostics.Process.StartWithShellExecuteEx(ProcessStartInfo startInfo)
   w System.Diagnostics.Process.Start()
   w System.Diagnostics.Process.Start(ProcessStartInfo startInfo)
   w DanTup.BrowserSelector.Program.LaunchBrowser(String url, Boolean waitForClose).

used configuration like this:
BrowserSelector.txt
also I've tested with quotes.

Works fine with Firefox, Vivaldi, Chrome.