1284374 - Keystrokes become out of order

Status: NEW

(Core :: DOM: Content Processes, defect)

Description

[Hugh Nougher [:Hughman]]

This is a very annoying problem I and others around me have noticed in the recent releases of Firefox. We have a (very badly made) 3rd party web program which makes this problem extremely prominent.

When typing into text fields (in webpages and search/address bar) the expected result would be: "This is an example"

What appears is like the following:
"thIS is an example"
"Thisisan  ex ample"
"This is anexample "
Note: Letters tend to be in order but most other keys will regularly end up in another order even though I just used the (most common) space/shift key example.

Observations:
- Since we have that bad webpage that generates a HUGE amount of garbage, the GC is continuously running/struggling.
- Slower the PC the worse the problem (wost seen was every non-letter keypress was in the wrong place).
- I would suspect that this is somehow being caused by the event queue going partially out-of-order.
- Turning off javascript.options.mem.gc_incremental has reduced the number of times the problem occurs but does still happen (and not related to when the browser pauses).

Comment 1

[:Gijs (he/him)]

Do you have a link to this website? Do you know if it uses Java or any other kind of plugin?

Comment 2

[Hugh Nougher [:Hughman]]

There is no flash or any other plugin used on the site.

Just 4.8MB of JS, 750KB CSS and 1.2MB of other stuff just to open the first page after login. Also just having that page in another tab while writing this has caused numerous typos of the style described.

The site is a subscribed web application so I doubt giving the URL will be of much use. http://app.mspmanager.com/

I can likely assist further if needed. Things like CC logs are definitely possible.

Comment 3

[:Gijs (he/him)]

(In reply to Hugh Nougher [:Hughman] from comment #2)
> The site is a subscribed web application so I doubt giving the URL will be
> of much use. http://app.mspmanager.com/

Is there a test/guest login we could use for this bug that doesn't have any significant privileges or something (NB: this bugreport is public, please don't post private (non-guest/test) credentials :-) ).

Does this reproduce on all OSes? Just Windows? Have you tried a clean profile?

Not sure a CC log would be useful... and also not sure at what level this problem happens - seems unlikely to be related to the location bar or frontend, more likely to be a core issue, either related to our general events processing or perhaps OS-specific ones (depends on the answers to the questions above. :-) ).

Comment 4

[Hugh Nougher [:Hughman]]

There is no guest login or such without paying lots of money. Might be able to organise a remote control login to a local PC here with my account if absolutely needed.

Also this bug was aimed at a more generic issue than just the site itself. The site just seems to be a great trigger for the bug to appear. Most likely stuffing a huge number of events + GC into the event queue it would show itself (Firefox is nearly always 1-2 solid CPU cores when this start going nasty).

Win10 is all we have available atm but I believe it was spotted once on a Win7 VM.

Clean profile obviously works better because it has less tabs/addons to overload Firefox with. It does appear after a while though (once this stupid web page uses a few 100 MB ram).

Comment 5

[:Gijs (he/him)]

Jim, do you have suggestions on how to triage this further and/or get a testcase?

Comment 6

[Hugh Nougher [:Hughman]]

I may have spotted a possible test case. Cannot confirm at this stage.

If you have IGC turned off as I do (to reduce the chance of this bug) try making the GC hang the browser of a few seconds. During the hang type stuff.

Comment 7

[Jim Mathies [:jimm]]

Hugh, what version of firefox are you seeing this in and do you have e10s enabled? (Please post your about:support text)

Comment 8

[Hugh Nougher [:Hughman]]

Attachment: Support

Versions that have been noted with the problem are at least release versions from Feb to now (others in company, various levels of addons). Also in beta 48 which I use currently. No e10s in this set.

I had previously used a Nightly with e10s (until said web app's date picker stopped working in it) and remember seeing similar typing problems but didn't take real notice at the time.

Attached is about:support. Note the gc_incremental is disabled in this as previously mentioned.

Comment 9

[Hugh Nougher [:Hughman]]

Attachment: Video showing the most noticeable issue

Hopefully this recording is going to showsome  issues with the typing to the screen.

I have definitely got at leastonep  roblem in this block of text.

See the attachment video of the entering of this text.

Comment 10

[Mike Conley (:mconley) (:⚙️)]

This sounds very similar to bug 1265324.

Comment 11

[ovidiu boca[:Ovidiu]]

Hugh do you think this bug is similar with bug 1265324, what Mike suggested?

Comment 12

[Hugh Nougher [:Hughman]]

There is definite similarities btu there is a few key points:
- The main testing computers here are NOT e10s (see attachment 8770769 [details]).
- This does not have to have backspace pressed at all to have the problem (as visible in attachment 8773122 [details]).
- This affects all non-letter characters including shift.

Comment 13

[Hugh Nougher [:Hughman]]

Hey I just had an idea. Trials still in progress but I think it could be related to (in my companies case) the Webroot Phishing and/or Identity Shields (includes keylog protection via injected dll).

I'll report results once there is any indication (if that is even possible while its still installed).

Comment 14

[Hugh Nougher [:Hughman]]

Attachment: Webroot settings in question

So after trying the Webroot change on a few PCs its looking very much like its caused by the "Identity Protection" features of Webroot. Attached screenshot shows the settings we have changed in this test.

With these settings off there is still the major pauses/hangs of Firefox caused by the mentioned web app but all typing is in the correct order! Yippee!

Comment 15

[Mike Conley (:mconley) (:⚙️)]

Hey Dirkjan,

Do you have the same Webroot software that Hughman has? Could this be causing your issue in bug 1265324?

Comment 16

[Dirkjan Ochtman (:djc)]

I'm pretty sure I don't; it doesn't sound familiar. Maybe the common cause could be some general kind of slowdown?

Comment 17

[Paul Brannan]

This bug (or perhaps a similar one) can also be triggered using "Find in page". While the browser is very busy (loading pages in other tabs, or still loading the page in the current tab), press Ctrl-F to find in page, type a phrase, and often the letters show up in the text box out-of-order.

I've wondered if this is related to Bug 1290493, where clicking "View image" in the context menu and then switching tabs can cause the image to load in the wrong tab; in both cases, firefox seems to be processing events out of order.