1314114 - Provide an option to keep WebExtension data on uninstall

Status: RESOLVED WONTFIX

(WebExtensions :: Frontend, defect)

Description

[Nancy Grossman]

Extension data will now be deleted when a WebExtension is uninstalled (bug 1213990). This is new behaviour for Firefox users, and it isn't always the right behaviour. For example, users commonly reinstall an extension they perceive to be malfunctioning (bug 1213990 comment 3). In some of these cases you do want to delete (some) storage before reinstalling to restore extension settings to a familiar state (bug 520142 comment 3). In others though deleting (all) storage is a disaster, because it deletes documents the user has created or compiled along with the extension settings (bug 1313422 comment 5). 

I would like to choose for each extension I uninstall whether to keep or delete its data. I think it should default to 'keep' for continuity with previous Firefox behaviour. I suggest a check box to control whether data is deleted when the extension (bug 1313422 comment 7).

There is already a preference to disable data deletion, but it applies to every uninstall - you can't easily choose to keep this extension's data but delete the rest - and it isn't exposed in the UI. A UI control is important. It reminds users that there may be unwanted side effects as well as providing a way to avoid them.

This has come up before in re preferences (bug 258301, bug 520142); the question was, what to keep and what to delete. "Delete Profile" lets you choose whether to delete files or not, with "Don't Delete Files" in place of the "OK" button. Firefox leaves profile data in place when it's uninstalled, though it once had a 'delete' option ("Remove my Firefox personal data and customizations").

Comment 1

[Caitlin Neiman [:caitmuenster]]

To be discussed at Jan 10 WebExtensions Triage meeting. 

Agenda: https://docs.google.com/document/d/18K97o1juaHSeYEkes1iMz8AayjuVkUuIK844ErGaa-c/edit#

Comment 2

[Kris Maglione [:kmag]]

We all agreed that this isn't something we want to implement. Data from storage.sync is always retained across installs, but other local storage data is expected to be deleted when the extension is uninstalled.