Mouse right click does nothing in 9.5.21’s Pool?

Title says it all

No issues here. Try running Cubase in Safe Start Mode and see if there’s any difference:
https://www.steinberg.net/nc/en/support/knowledgebase_new/show_details/kb_show/safe-start-mode-resetting-the-cubase-preferences.html

Sweet! Thanks Romantique TP ^^