This add-on creates a Firefox profile called ‘zap-client-profile’ and sets it as the default profile that ZAP will use. This profile enables the ZAP Firefox extension for all sites.
If you choose to use another profile then you will need to manually approve the ZAP extension for every site you use it for, every time you launch a browser from ZAP.
This is a Firefox restriction - for more details see Bugzilla Bug 183609.
If you want to use the ZAP Firefox extension in your own containers then you may find that it does not work out of the box.
It should work fine in the ZAP Docker Images as the ‘zap-client-profile’ is added to them. If you create your own container images then you may need to include it as well.
For more information see