Firefox hangs every time I start it after Installing uBlock origin

[uptonn]

Describe the issue

Every time when I start Firefox it doesn't respond to anything (crashes) for about 20 seconds, only happens when I install uBlock Origin, it happened to me since version 1.9.4. I waited for version 1.9.6 to be fixed but seems latest version doesn't solve the problem.

• Browser/version: Firefox/48.0.2
• uBlock Origin version: 1.9.6 with default filters

PS: I also removed all other addons except uBlock, the problem still exists.

[gorhill]

You will have to investigate on your side, there is no such issue reported elsewhere. See what the browser console says. Also, consider what might be specific on your side, like anti-virus, sandboxie, etc.

[uptonn]

this what console says when uBloc Origin installed:

this what console says when it is disabled:

[gorhill]

Interesting. I get this error on a random basis, and it causes uBO to start malfunction -- related issue #1713.

Frankly, I don't know what to make of it. I think this should be reported to FF issue tracker -- surely someone in there has better insight of what is going on than I can provide.

By the look of it, it is as if a modal window is opened in uBO's iframe context -- which is not supposed to happen -- hence the error. uBO of course never opens a modal window, let alone open one in its chrome code, so for some reasons the browser itself is doing this, and this causes the issue.

The above speculation is supported by https://bugzilla.mozilla.org/show_bug.cgi?id=1167575, which is what the dev console shows as happening.

Bottomline: we need insight from FF devs, I don't know why this condition arise.

[gorhill]

I commented about the case here in bugzilla, awaiting feedback.

[gorhill]

Do you have user preferences which differ from default ones?

[uptonn]

@gorhill
no I didn't change anything in uBO settings its all defaults, I also didn't change settings in Firefox

[gorhill]

When you launch Firefox and the issue occurs, are there any tab loading? If so, what URL?

[uptonn]

Yes, ATM I have default home page set to: "https://www.google.com/ncr" but even when I change it to (Show a Blank page) same result. FF still Crashes for few sencods

[gorhill]

Similar issues already reported at bugzilla or elsewhere:

• https://bugzilla.mozilla.org/show_bug.cgi?id=1083803
• https://bugzilla.mozilla.org/show_bug.cgi?id=1186727
• https://www.bountysource.com/issues/25224778-about-blank-the-script-with-alert-function-after-the-restart-the-browser-hangs

[gorhill]

If you launch FF without uBO, then enable uBO after FF launched, do you still have the issue?

The fact that you can reproduce at will is kind of precious, this means surely there must be a way to try to find out what is causing the creation of a modal window at launch time.

[Tmp341]

Check your crashes with about:crash and/or try creating a new profile. Sometimes settings cause those crashes. You can do this with about:profiles

[gorhill]

Actually, try to delete uBO's SQL database, to force uBO to re-generate it. Maybe a corrupted SQL file is behind this. See https://github.com/gorhill/uBlock/blob/master/dist/README.md#firefox for the location of the SQL file.

[uptonn]

I might go to hell for doing this because I think the bug isn't 100% identified yet, but when I was googling about how I solve Firefox issues I found about resetting Firefox might solve the problem, so I did "Refresh Firefox" in about:support and then Installed uBO after that the problem is solved and I can't reproduced it, I'm very sorry if what I did will no longer help catch this mysterious bug.

[uptonn]

@gorhill
previously when I launched FF without uBO enabled it started fast, but as soon as I Enable it, FF crashes for few seconds, I hope that helps.

[gorhill]

Now I am looking more closely at your screenshot and realize I was wrong to say it's similar to #1713, it looks like uBO was timing out on loading the compiled filter lists.

[coladict]

@uptonn open about:config filter for e10s. The values you'll see there will tell you if you're one of the test subjects for the new multiprocess Firefox which requires a migration to the new API in #622 to be compatible in the near and distant future.