1334016 - Malformed JSON file breaks about:support

Status: RESOLVED WONTFIX

(Toolkit :: Add-ons Manager, defect, P5)

Description

[James Kitchener (:jkitch)]

Attachment: experiments.json

When the attached file is inserted into the profile directory, all fields of about:support are listed as blank.

Browser console reports the following error

15:25:38.367 A promise chain failed to handle a rejection. Did you forget to '.catch', or did you forget to 'return'?
See https://developer.mozilla.org/Mozilla/JavaScript_code_modules/Promise.jsm/Promise

Date: Thu Jan 26 2017 15:25:36 GMT+1030 (Cen. Australia Standard Time)
Full Message: Error: uncaught exception: Invalid header (no magic number) - Data: C:\Users\James\AppData\Roaming\Mozilla\Firefox\Profiles\dc169xr6.default\experiments.json
Full Stack: postMessage@resource://gre/modules/PromiseWorker.jsm:323:17
TaskImpl_run@resource://gre/modules/Task.jsm:320:42
Handler.prototype.process@resource://gre/modules/Promise.jsm -> resource://gre/modules/Promise-backend.js:935:21
this.PromiseWalker.walkerLoop@resource://gre/modules/Promise.jsm -> resource://gre/modules/Promise-backend.js:813:7
this.PromiseWalker.scheduleWalkerLoop/<@resource://gre/modules/Promise.jsm -> resource://gre/modules/Promise-backend.js:747:11
 1 (unknown)

Comment 1

[James Kitchener (:jkitch)]

Attachment: screenshot

Screenshot of the affected about:support

Comment 2

[James Kitchener (:jkitch)]

According to my backups, the file achieved its current form on 2016-11-28, replacing a JSON/mozLz40 file of the same length.

Comment 3

[George K.]

I have the same issue, though my broken .json file is a few bytes larger.

My Browser Console reports only the following when opening about:support:

Error: WebGL warning: Failed to create WebGL context: WebGL is currently disabled.  Troubleshoot.jsm:472:18
Error: uncaught exception: Invalid header (no magic number) - Data: C:\Users\(path to my profile)\experiments.json  (unknown)

Comment 4

[George K.]

Sorry for the bugspam. I just realized that I forgot to confirm that deleting the broken experiments.json file and restarting Firefox resolves the issue.

Comment 5

[Shane Caraveo (:mixedpuppy)]

This is no longer reproducible based on the STR provided, the file was probably something we had in the past that has since changed.