1567576 - choosing profile from Profile Manager causes "Couldn't load XPCOM" error

Status: RESOLVED INCOMPLETE

(Toolkit :: Startup and Profile System, defect, P5)

Description

[a]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:69.0) Gecko/20100101 Firefox/69.0

Steps to reproduce:

On Win10 64.

start firefox with either

1. no default startup profile
2. -P
   in order to bring up the profile manager, and then selecting a profile, causes firefox to give a vague "Couldn't load XPCOM" dialogue box. Then that firefox instance won't load any pages, including about: pages.

This is true for completely new profiles, as well as a variety of profiles I used in the past. I tried

1. backing up and deleting the local/roaming/locallow appdata folders
2. installing firefox fresh, I tried 68.0, 68.0.1 and 69b6. all have the same problem with and without fresh profiles

Not using the profile launcher seems to work fine.

I also don't appear to have the same problem as any of the older instances of people having XPCOM errors.

I don't know if this is related, but I used to use 1 profile launched regularly, where clicked links in other programs would open in it, and a 2nd browser profile launched with -no-remote (as far as I know this used to be the only way to launch several browser profiles, I do not know if this has changed). After a recent version, (maybe 67?), it started acting in a way to where once I started the second instance with -no-remote, the first instance also acted like -no-remote is on.

The only thing I can think of that I've changed on my system recently is that I installed the CUDA devkit, which added a ton of dlls to the path. This problem started after I rebooted after installing that, but it may have been a windows update that I didn't notice or something..

Actual results:

xpcom error

Expected results:

no xpcom error

Comment 1

[a]

also: i'm not positive, but i believe was running 68 or 68.0.1 (unsure which, sorry) for a few days before this occurred, it wasn't after a firefox update

Comment 2

[Alice0775 White]

@reporter,
Can you please attach a result of about:support (Help – Troubleshooting Information)?

Comment 3

[a]

Attachment: about:support

about:support from a relatively clean-ish profile that still has the issue. not sure if i changed anything on this profile from default or not

Comment 4

[a]

also i gotta say that, just, in general, not just related to my specific issue, i'd consider the extreme unhelpfulness of the 3-word "Couldn't load XPCOM" error message is basically a bug of its own.

Comment 5

[Dave Townsend [:mossop]]

In about:support can you give us the exact text of "Application Binary"?

Comment 6

[a]

C:\Program Files\Mozilla Firefox\firefox.exe

Comment 7

[Dave Townsend [:mossop]]

I can't reproduce the issue here which is going to make figuring this out quite a challenge.

You sound like maybe you're technically minded though and it might reveal a lot if you could capture an event log of Firefox doing this with process monitor (https://docs.microsoft.com/en-us/sysinternals/downloads/procmon) and make it available. It is possible, that that may reveal information about what is going on on your computer at the same time, if you aren't comfortable putting that in this public bug report then you could email it directly to me if you feel happier about that.

Comment 8

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

The priority flag is not set for this bug.
:mossop, could you have a look please?

For more information, please visit auto_nag documentation.

Comment 9

[Daniel Cicas [:dcicas], Release QA]

Hello,

I managed to reproduce this on in Fx 73.0b4. I found a reliable way to reproduce this issue 100% of the time.

1. Custom install path for firefox (eg. Desktop/Random Folder/firefox)
2. Open Firefox with firefox -p
3. Create new profile in folder Desktop/Random Folder BUT do NOT start Fx.
4. Delete the newly created profile (when the prompt appears select DELETE FILES).
5. Close profile manager.
6. Try to open firefox again using the profile manager.

The "Couldn't load XPCOM" error appears.

As far as I can see it deleted half of my firefox folder and any other folders I had in "Random Folder"

Comment 10

[Dave Townsend [:mossop]]

(In reply to Daniel Cicas [:dcicas], Release QA from comment #9)

Hello,

I managed to reproduce this on in Fx 73.0b4. I found a reliable way to reproduce this issue 100% of the time.

1. Custom install path for firefox (eg. Desktop/Random Folder/firefox)
2. Open Firefox with firefox -p
3. Create new profile in folder Desktop/Random Folder BUT do NOT start Fx.
4. Delete the newly created profile (when the prompt appears select DELETE FILES).

This just sounds like bug 302087. It's not clear that this is what the reporter is doing though.

Comment 11

[Wayne Mery (:wsmwk)]

Reporter,

do you still see this when using a newer version?

Comment 12

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

A needinfo is requested from the reporter, however, the reporter is inactive on Bugzilla. Closing the bug as incomplete.

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