1922436 - Newtab if a malformed blocked topsite pref issue

Status: NEW

(Firefox :: New Tab Page, defect, P2)

Description

[Scott [:thecount] Downe]

The pref "browser.topsites.blockedSponsors", if it happens to be malformed, it'll fail when we parse it and cause topsites to now show.

We don't actually know how to reproduce this yet, but we have had 1 instance of maybe it happening.

Manually changing the pref however, can trigger the issue.

I think it's worth fixing just in case, at the very least it strengthens our system a bit, but might actually be fixing an odd and old and tricky bug.

I think the solution is if the parse fails, catch it, and fallback to an empty array.

Comment 1

[Scott [:thecount] Downe]

To test:

1. Set "browser.topsites.blockedSponsors" to an empty string. Don't delete it or clear it. Specifically an empty string. Can also be a space or another string that won't parse into valid json.
2. Restart the browser.
3. Open/refresh newtab.

Expected: should still see topsites.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:thecount, could you have a look please?

For more information, please visit BugBot documentation.

Comment 3

[Maxx Crawford [:maxx]]

Attachment: Bug 1922436 - Confirm browser.topsites.blockedSponsors is an array r?thecount