Hi,
I’m currently trying to enable some plugins available in “manage plugins” window but when i set them to ENABLE and click OK, nothing is added to my “Effect Menu > …” 
I use Ubuntu 20.10 and audacity 2.4.2
thx for any help
Which plug-ins?
Limiter, equalization for example… but there are several I the menu that I could enable as by default they are disabled, but once I click on OK button, nothing change.
Do all of the effects listed here enable: https://manual.audacityteam.org/man/effect_menu_nyquist.html
No they are not enabled.
I remove everything and installed clean new copy via SNAP of v3.0.2… All plugins are installed but for an obscured reason, I have some plug ins in english and some in french while I setup application language interface in ENGLISH (preferences > Interface)
There seems to be a problem with the Snap package: https://github.com/diddlesnaps/audacity/issues/17
I’d suggest that you completely remove the Snap version of Audacity, then:
1.Delete the hidden folders:
~/.audacity-data
~/.audacity-files
(where “~/” means your home folder)
- Install Audacity 2.4.2 from a Terminal window with:
sudo apt install audacity
Then look in the Effect menu to see what effects are installed. In particular, what effects are enabled in the section at the bottom of the Effect menu below “Wahwah”.