Removal of addon does not remove the "open tab in new container" option from the right click menu on a link

[lohanirahul]

Before submitting a bug report

• I updated to the latest version of Multi-Account Container and tested if I can reproduce the issue
• I searched for existing reports to see if it hasn't already been reported

Step to reproduce

1. Install the add-on.
2. Create new container.
3. Right click on any link. The option "Open new tab in container" is present.
4. Remove the add on.
5. Restart firefox if you want. Does not help.
6. Right click on any link. The option "Open new tab in container" is STILL present.

Actual behavior

I did not like the addon so removed it. But its trace in the form of "Open New Tab in Container" in right clicking on any link was still present with my container name. Clicking on it takes me to firefox add on gallery.

Expected behavior

The right click context menu should not have the option to open tab in new container once I remove the addon

Additional informations

To solve my problem, I installed the add on again. The container name was populated in the addon (should not happen). I removed it. and Deleted the addon again.

Provide a copy of Troubleshooting Information page (optional)

No response

[ks1322]

Related to #534 and #2632