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Mac OS: System log being filled with various "CGContext..." errors

  • 11 ردًا
  • 50 have this problem
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  • آخر ردّ كتبه cor-el

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I've been troubleshooting an occasional FF26 hang (whereby the entire browser goes unresponsive for 10-15 seconds) and took a look at the system log.

I'm running Mac OS Mavericks 10.9.1. The log is absolutely **inundated** with messages like this:

Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextConcatCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextClipToRect: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextConcatCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextTranslateCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextScaleCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextSetInterpolationQuality: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextDrawImage: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextTranslateCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextScaleCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextSetShouldAntialias: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextConcatCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextClipToRect: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextConcatCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextTranslateCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextScaleCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextSetInterpolationQuality: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextDrawImage: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.

This message seems to be associated with scrolling - i.e. it only happens when I scroll the view. Every time I scroll, a good page or two of these messages are generated.

Is this relevant, and how can it be fixed? My syslog is growing abnormally large due to this.

I've been troubleshooting an occasional FF26 hang (whereby the entire browser goes unresponsive for 10-15 seconds) and took a look at the system log. I'm running Mac OS Mavericks 10.9.1. The log is absolutely **inundated** with messages like this: <pre><nowiki>Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextConcatCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextClipToRect: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextConcatCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextTranslateCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextScaleCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextSetInterpolationQuality: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:07 mikebookpro.local firefox[12150]: CGContextDrawImage: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextTranslateCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextScaleCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextSetShouldAntialias: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextConcatCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextClipToRect: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextConcatCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextTranslateCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextScaleCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextSetInterpolationQuality: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. Jan 24 10:19:08 mikebookpro.local firefox[12150]: CGContextDrawImage: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. </nowiki></pre> This message seems to be associated with scrolling - i.e. it only happens when I scroll the view. Every time I scroll, a good page or two of these messages are generated. Is this relevant, and how can it be fixed? My syslog is growing abnormally large due to this.

Modified by cor-el

All Replies (11)

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Try to disable hardware acceleration in Firefox (you need to close and restart Firefox).

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I'm having the same onslaught of errors, with the 10 second hangs, also on 10.9.1. I did not have hardware acceleration enabled, and safe mode made no difference. Any ideas?

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I'm on 10.6.8 and have been getting truckloads of various Firefox-related "CGContext" errors as well. After a few hours of troubleshooting, here are some of my findings:

  • The first occurrence of the errors in my Console logs was on December 11, 2013 at 12:06pm (Eastern).
  • Over the last two months there have been literally hundreds of thousands of these entries (if not millions).
  • As Karunamon mentioned, there's a direct correlation between the errors and browser scrolling. One thing I've noticed is that the errors are only triggered when the distance scrolled is equal to or greater than the height of what's visible in the browser window/viewport. In other words, the errors don't show up if you only scroll enough to move a few lines of text up. You have to scroll enough to move everything you're currently viewing up/down. (So technically you could slowly scroll through an entire page in small increments without triggering the errors.)
  • They only occur with Firefox browser scrolling; other types of scrolling (such as iFrames within the browser) seem to be fine.
  • The errors appear in blocks of 16 lines at a time. Although they aren't always in the same order, they always reference the following 8 "CG" elements:
  1. CGContextTranslateCTM: invalid context 0x0
  2. CGContextScaleCTM: invalid context 0x0
  3. CGContextSetAlpha: invalid context 0x0
  4. CGContextSetShouldAntialias: invalid context 0x0
  5. CGContextConcatCTM: invalid context 0x0
  6. CGContextScaleCTM: invalid context 0x0
  7. CGContextSetInterpolationQuality: invalid context 0x0
  8. CGContextDrawImage: invalid context 0x0

I've tried disabling plugins, extensions, safe mode, etc but haven't had much luck. (And no, hardware acceleration is not enabled.)

As others have said, these really seem to be piling up, and are taxing machine resources every time browsing scrolling is used. So any suggestions or assistance would be greatly appreciated.

[I updated from v26 to v27.0.1 yesterday. I can't remember when I went from v25 to v26, but I suppose there's a chance it was after December 11; meaning the issue could be present across at least three versions.]

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Like gatorfantom above, I'm running OSX 10.6.8 on my MacBook and am having the exact same issues. It does indeed seem to be related to scrolling. In going back through my console messages I can see that in affected FF v26 and v27. Just today, in about 6 hours of use, over 1500 log entries have been created re this issue. Anyone have any thoughts?

PS: My hardware acceleration is disabled.

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I have been having this problem too, which seems to have been causing Firefox to consume unusually large amounts of memory. More than 4000 error messages were being logged every 30 minutes, which certainly can't help performance.

I just now reset Firefox, which of course removed all of my add-ons, and the problem has stopped.

I will add the extensions back in one by one to see if the problem returns. Fingers crossed!

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mlbdenver, did you have any luck in identifying the add-on that was causing the issue?

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I have tried disabling all plugins and extensions and the problem remains. I have not yet tried doing a full reset, but if I do I'll report back here.

PS: Since my note above I've upgraded to OS X 10.7.5 (the latest OS my old MacBook can handle), and am now running FF v.28.

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UPDATE - 3/31/14

GREAT NEWS

I updated to v28 this morning at 10:47am, and since then I have yet to see any type of Firefox-related "CGContext" errors or notices in Console. (Yay!) I will continue to monitor things as the day goes on and will report back if the errors return, but so far it looks like something in the v28 update fixed the problem.

@Kadir: As BFox mentioned, we don't think this was a plugin issue because both of us had previously tried disabling them, booting in Safe Mode, etc -- and didn't see a difference. The only thing I didn't try was a "reset", though I did try creating a new, separate profile -- but no luck with that either.

Out of curiosity I just started looking through the list of bugs fixed in the v28 release, but: A) the types of programming discussed in those bug reports is beyond my level of understanding, and B) there are almost 4,000 of them.

If someone else identifies the source of the problem, I'd love to know what it was.

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@gatorfantom (and all): I think I found the bug which has been resolved. Although I still had the problem with my version of FF 28.0 (which I downloaded on 3/23), and the problem persisted after resetting, I've now downloaded the FF v29 beta. The problem has been fixed.

Here's the bugzilla entry Bug 951443 - CGContext warnings with empty clip

The issue appears to have been in the mozillla core, as opposed to FF itself which may explain why your v28 is fixed and mine (download a week earlier) wasn't.

For anyone else having this CGContext error, try a fresh install of v28. If that doesn't work for you, v29 will. It's available in beta now, and should be fully released the week of April 29.

Modified by B.Fox

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I am super embarrassed to say that something I did that day fixed the problem for me. I was having overall system slowness, so I did a bunch of things, and now I can't figure out what I did. I've even gone through my browsing history of that whole day for a clue.

One troublesome plug-in for me was Google Earth, which I removed. I have NO IDEA if that is what fixed it.

I will keep looking for other clues. Now if I could just get AddressBookSourceSync to stop jamming my log with errors...

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Note that on Mac such issues can also be caused by IPv6.