Flickering windows Google Chrome and Firefox but not Safari

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Level 1

49 points

Flickering windows Google Chrome and Firefox but not Safari

Tonight, both Google Chrome and Firefox windows flicker particularly up on the menu bar. I updated Firefox 71.0 and Google Chrome is at 79.0.3945.79. Safari does not flicker.

Earlier today, my cursor started jumping all over the window so I managed to do a SAFE boot which stopped the cursor jumping but I have to believe the two phenomena are related.

Yesterday, I could watch Netflix on Chrome with smoothly moving picture and synchronized sound. Tonight, the same video runs slowly, jumps from picture to picture and there is no sound. The same is true on Firefox. Because my computer and system are so old, Netflix movies will not run on Safari but Chrome has been working fine.

iMac 27", macOS 10.13

Posted on Dec 12, 2019 8:38 PM

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Answer 1

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BDAqua

Level 10

245,165 points

Dec 12, 2019 8:50 PM in response to Gil Woolley

Safe Boot from the HD, (holding Shift key down at startup), does the problem occur in Safe Mode?

Safe mode attempts to repair Disks & clears lots of caches, so if Safe Mode works try again in regular boot.

˜What all 3rd party extensions are you running?

EtreCheck is a simple little app to display the important details of your system configuration and allow you to copy that information to the Clipboard. It is meant to be used with Apple Support Communities to help people help you with your Mac.

http://www.etresoft.com/etrecheck

Pastebin is a good place to paste the whole report...

https://pastebin.com/

Workable but harder for me to work with...the Note tool on the bottom of this editor's toolbar, as shown in the image, to copy and paste the output from EtreCheck.

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Answer 2

Gil Woolley Author

Level 1

49 points

Dec 12, 2019 10:42 PM in response to BDAqua

SAFE boot did not stop the flickering in Chrome.

I think that the flickering in Firefox changed. Instead of being mostly in the menu bar, it instead appeared on left and right sides of the window. Became more pronounced and easier to see when I selected Netflix but the menu bar was doing some flickering before I selected Netflix.

I ran the latest version of EtreCheck before I checked Chrome and Firefox. Not a good prognosis for my aging iMac. Failing hard drive. I have two bootable backup drives external. One by Carbon Copy Cloner and the other by SuperDuper.

I have saved the complete Etrecheck and pasted it into Pastebin but how do I link this email to it? I pasted it into Pastebin but do not see how I link to it here. So I also pasted it below.

gil_woolley iMac Flickering Chrome and Firefox

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Answer 3

Gil Woolley Author

Level 1

49 points

Dec 13, 2019 10:31 AM in response to BDAqua

The problem still occurred in SAFE mode. It occurred with Chrome and Firefox.
I booted from one of my bootable external hard drives. There is no flickering in Chrome. This external has not yet had Firefox installed so I can't test that.
For some different reason, the drive which would have had Firefox on it would not boot though I selected it in Startup Disk. Not a part of this problem but that is why I did not test in Firefox.
I'm not quite sure what you mean by 3rd party Extensions. The two login items are Audio Hijack 3 Schedule Helper and CCC User Agent.
Disk Utility found nothing wrong with my internal hard drive but clearly the problem occurred running from internal hard drive and not from external hard drive.
I guess this eliminates a graphics card caused problem as the same card is operating from whichever disk I boot from.

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Answer 4

BobHarris

Level 9

55,007 points

Dec 13, 2019 5:14 AM in response to Gil Woolley

Try gfxCardStatus is a free menu bar application that keeps track of which graphics card your MacBook Pro is using at any given time.

https://github.com/steveschow/gfxCardStatus/releases/download/v2.4.4i/gfxCardStatus.app.zip

You may have a failing discrete GPU.

In Safe mode the screen may flicker but it should be different from normal boot mode flicker.

But just to be sure, you should check that what you think is a normal boot mode is not actually safe mode:

Verify Safe mode via Applications -> Utilities -> System Information -> Software -> Boot Mode -> Safe vs Normal

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Answer 5

Gil Woolley Author

Level 1

49 points

Dec 13, 2019 11:00 AM in response to BobHarris

The problem computer is a mid 2010 27" iMac. The flickering does not occur when I boot from a bootable external hard drive. I've now tested that on Chrome and Firefox. No flickering with either browser when running from the external drive.

I am going to restart from the external drive and run Etrecheck again.

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