I just installed qtractor 0.9.12-1build1 from the official Focal Fossa repository. All the menus are blank. Both the top bar menus and the right-click menus. I wonder if it's something wrong with QT but I have other QT applications and they look fine. For example, Cadence looks fine. Any ideas?
right-click menu
sorry, v0.9.12 is a way too old to support
anyway, try launching with the command line, like
qtractor -style Fusion; on more radical solution would be to wipe out the current configuration altogether: try rm~/.config/rncbc.org/Qtractor.confand restart.Yes, 'qtractor -style Fusion' works. Thank you.
What other themes can I try other than Fusion?
And what is the last version of qtractor to use QT5?
for other widget styles see View>Options...>Display>Custom>Style theme; take care that at least one of them listed leads to the blank menus issue.
qtractor can still be built to Qt5, but upstream support for it is being phased out; consider to upgrade to a more recent distro; anyway, 20.04 (focal) reaches EoL in just a few months.