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Firefox hangs constantly, including Troubleshooting page (Mac)

  • 4 replies
  • 1 has this problem
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  • Last reply by FredMcD

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This is driving me absolutely crazy. I use FF on at least 4 different Macs, and for some reason a fresh install on a brand new MacBook Pro (2018 USB-C) is hanging constantly. Works fine on every other Mac I have. All Macs on are the latest OS (10.14.2), all have the latest FF (64.0.2). But for some reason this one instance will not work.

On some sites, it seems to hang randomly. I usually have several tabs pinned and open, sometimes those tabs will hang when they reload themselves (Outlook.com, Remember the Milk, Yahoo mail, etc). Sometimes a website in a new tab will hang - but if I close the tab and go to the same site/link in a new tab, it will load fine. Once one tab hangs, it seems to cause other tabs to start hanging, but not 100% sure about that.

But there are two sites that ALWAYS cause it to hang: Amazon.com and the Firefox Troubleshooting page. For Amazon, that one tab will hang and I can usually close that tab (takes a few seconds to close). For Troubleshooting page, it locks up the whole app and I have to force quit.

Safe mode DOES work. I can get to Amazon and Troubleshooting page. But on a clean fresh install with no extensions installed (or enabled, see below), these pages will still hang. Is there another difference with Safe Mode?

Note that this is on a laptop that is provided by my employer and it's possible that there's some other software involved. For example, there are two plugins already there even on a fresh install: OpenH264 Video Codec provided by Cisco Systems and Widevine Content Decryption Module provided by Google. I can't seem to remove them. (I have another Mac at home that runs on Cisco's network, but I don't know what it has installed - not there now, I can check this later if it's relevant.) However, my previous work laptop (2015 MacBook Pro) did not have these problems - also latest OS and latest FF.

I've tried uninstalling and reinstalling (delete the app, remove the Application Support folders for Mozilla and Firefox, remove my profile). I've tried Refreshing Firefox. Nothing works except Safe Mode.

I've attached the troubleshooting JSON info while in Safe Mode. I do have LastPass installed now, but I tested without it, too.

Please help! I depend heavily on Firefox (bookmarks sync and some key plugins) and I'm not willing to use anything else, unless I just can't fix this.

This is driving me absolutely crazy. I use FF on at least 4 different Macs, and for some reason a fresh install on a brand new MacBook Pro (2018 USB-C) is hanging constantly. Works fine on every other Mac I have. All Macs on are the latest OS (10.14.2), all have the latest FF (64.0.2). But for some reason this one instance will not work. On some sites, it seems to hang randomly. I usually have several tabs pinned and open, sometimes those tabs will hang when they reload themselves (Outlook.com, Remember the Milk, Yahoo mail, etc). Sometimes a website in a new tab will hang - but if I close the tab and go to the same site/link in a new tab, it will load fine. Once one tab hangs, it seems to cause other tabs to start hanging, but not 100% sure about that. But there are two sites that ALWAYS cause it to hang: Amazon.com and the Firefox Troubleshooting page. For Amazon, that one tab will hang and I can usually close that tab (takes a few seconds to close). For Troubleshooting page, it locks up the whole app and I have to force quit. Safe mode DOES work. I can get to Amazon and Troubleshooting page. But on a clean fresh install with no extensions installed (or enabled, see below), these pages will still hang. Is there another difference with Safe Mode? Note that this is on a laptop that is provided by my employer and it's possible that there's some other software involved. For example, there are two plugins already there even on a fresh install: OpenH264 Video Codec provided by Cisco Systems and Widevine Content Decryption Module provided by Google. I can't seem to remove them. (I have another Mac at home that runs on Cisco's network, but I don't know what it has installed - not there now, I can check this later if it's relevant.) However, my previous work laptop (2015 MacBook Pro) did not have these problems - also latest OS and latest FF. I've tried uninstalling and reinstalling (delete the app, remove the Application Support folders for Mozilla and Firefox, remove my profile). I've tried Refreshing Firefox. Nothing works except Safe Mode. I've attached the troubleshooting JSON info while in Safe Mode. I do have LastPass installed now, but I tested without it, too. Please help! I depend heavily on Firefox (bookmarks sync and some key plugins) and I'm not willing to use anything else, unless I just can't fix this.

All Replies (4)

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I opened the console in regular mode and captured the logs from startup and an attempt to load Amazon.com. See attached. Not much there. If I try the same thing with Troubleshooting page, I get no output and FF hangs.

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Interesting.

It could be Hardware Acceleration. How to disable Hardware Acceleration {web link}

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I've found the culprit - almost by accident: DisplayLink. I have a HumanScale dock and use DisplayLink to drive twin 2k monitors off that dock. The dock also has Ethernet and USB. Connected via USB-C cable (which also has power delivery). Great in concept, but something's causing problems for Firefox.

I went to a meeting, so unhooked from the dock. Now I could go to Amazon, Troubleshooting, whatever and it worked fine. There's still ONE other difference, but I don't think it's the issue... the dock provides network. Maybe WiFi works but wired doesn't. I'll to test that another time. But I don't think that matters because there are other issues going on that I thought were unrelated, but now I'm pretty sure it's not...

Display problems. Note that I have the laptop lid closed, so I was just using the two 2k monitors. I was also having trouble disconnecting from the dock - when I do, the laptop still thought it was connected to two screens and the main laptop display was black when I lifted the lid (the touch bar showed the display option: mirror or extend). I couldn't get it to show anything. I had to hard reset the Mac (hold the power button). This happened several times. Re-connecting the USB-C cable didn't fix it, either - all screens were black. I am now using two USB-C dongles to drive the monitors via HDMI and everything works great.

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I suggest you contact Mac support as well as DisplayLink. And any others that can help.

Please keep us posted.