UPDATE: This issue has been resolved probably in the Summer 21 Release
Minimal working example to demonstrate a bug in deploy and updateMetadata where installed QuickActions cannot be updated
Clone this repository.
Create a scratch org and install a dummy managed package
yarn
yarn developRetrieve an installed QuickAction
sfdx force:source:retrieve -m "QuickAction:mdapidummy2gen__Vehicle__c.mdapidummy2gen__Deprecate"Change the uiBehaviour to Required and try to deploy the installed QuickAction
perl -p -i -e 's|<uiBehavior>Edit</uiBehavior>|<uiBehavior>Required</uiBehavior>|' force-app/main/default/quickActions/mdapidummy2gen__Vehicle__c.mdapidummy2gen__Deprecate.quickAction-meta.xml
sfdx force:source:deploy -m "QuickAction:mdapidummy2gen__Vehicle__c.mdapidummy2gen__Deprecate"Notice the error message saying
[CANNOT_MODIFY_MANAGED_OBJECT] Cannot modify managed object: entity=QuickActionDefinition, component=09D0V000001Da5y, field=OptionsCreateFeedItem, state=installed
but we did not change the OptionsCreateFeedItem field.
Applying this change using a the Setup Menu just works fine.