When the setting for cookie lifetime (in the "Privacy & Security" tab) is changed to "Keep until they expire", localStorage access is not consistent. I've created a demo that highlights this issue: https://github.com/wyattjoh/local-storage-demo It is also deployed here: http://brash-page.surge.sh/ Essentially, when the "Keep until **I close Firefox**" is set, localStorage is not properly shared across tabs. Using the demo code I provided, you can follow these steps to reproduce: 1. Ensure that about:preferences#privacy has "Firefox will **Use custom settings for history**" and under "Accept cookies from websites", you have "Keep until **they expire**" set. 2. Open a tab to view the contents of the edit box. Click the "Edit with Popup" button. 3. Enter text in the popup. 4. Click "Save to Local Storage" 5. Close the window. 6. Duplicate the window. 7. Notice that your edited content is shown in the new tab. 8. On about:preferences#privacy, change "Keep until **they expire**" to "Keep until **I close Firefox**" 9. Repeat steps 2-6, but notice that the content did not change to the newly edited content that you changed when you repeated step 3, instead, it is the previous content that you saw at step 7, before you changed the Firefox preference. This to me represents an incorrect behavior of the setting, as I didn't even have to close anything at any point to see the issue.

Johann, you've dealt with storage-related bugs recently. Any idea what component we should move this to?

Yeah there's some inconsistency here, it's pretty edge-casey, but I can get inconsistent local storage state on these two sites when flipping the "keep until" pref back and forth, too, even on reloading the pages. It works correctly if I close and re-open one of the tabs. Jan, Tanvi, do you have any thoughts or ideas on this? It doesn't strike me as terribly important, but it would be good to find out what's happening here.

I don't know this code, so don't know why it would be happening. But does seem pretty edge-casey, as you say. So I think we keep it as a low priority bug for now.