In avidemux Main menu: Help:
QtScript Reference <- click
In terminal window this message is displayed:
Quotegvfs-open: file:////usr/share/avidemux6/help/QtScript/index.html/: error opening location: Error when getting information for file '//usr/share/avidemux6/help/QtScript/index.html': No such file or directory
index.html The main help page for avidemux is missing. All others files are probably there/created/present.
On your linux system copy this link below
file:///usr/share/avidemux6/help/QtScriptQT4/functions.html
and paste it in to your browser address bar. This would most likely bring up the help page:
Avidemux 2.6 Scripting Reference: all functions.