Try the solution for the pencil icon on Mac:

• Delete the Firefox icon from the dock.
• Create a new icon by dragging the Firefox application to the dock.
• [/questions/883573]

deleting it from the dock and dragging the icon over worked. Thanks ! I don't know why deleting it from the dock and then starting up Firefox didn't work, but this did (and I did try searching around before asking, but I could not find it).

Thanks !!

I just installed the latest High Sierra update (10.13.2) and it is doing it again. The icon reverted to the generic icon with a capital "A" again. This time , deleting the icon from the dock and dragging Firefox to the dock again didn't work. The icon is still a light blue rectangle box with a thin white border around it and a capital "A" that is made from a pencil, paintbrush and ruler. I also tried something that has worked for me in the past, which is to delete the icon from the dock and then start up Firefox from the Applications folder, but that doesn't result in a Firefox icon either.

OK, my computer is playing tricks on me. I just tried this yet again. Firefox was not in the dock. I dragged Firefox from the Application folder into the dock and it worked this time (?????). It did not work the last two times I had tried it since this latest High Sierra update just a day or so ago. Today, it worked. Again. I don't get it. Maybe it had to be out of the dock for at least a day for it to work again this time ? I have no idea.

This is unfortunately not working anymore. Sometimes it works and sometimes it doesn't. In the last couple of days, it went back to displaying the grey box with an A as the icon. Removing the icon from the dock and dragging Firefox from the Application folder simply does not work today (Sunday, December 24, 2017). I have tried it multiple times and it doesn't work. It turns back to a grey square with an A the second I drag it back to the dock.

Please Refresh but do this 1st:

• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer
• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

then

• https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

TEST....... If no issues then Extensions which need to be added back in 1 at a time and tested ..... Or it is your Profile : Make a new one and test ...:

• https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

If is your Profile :

• https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile
• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Note: Any customization will revert back to default, you will also need to reinstall Extensions.

Please let us know if this solved your issue or if need further assistance.

If that fails to fix the icon when dragging it out uninstall Firefox and delete the Mozilla Firefox Folders but not your Profile Folder. https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data then reinstall with a Full Version Installer from your source or from : https://www.mozilla.org/firefox/all/

it wasn't changing the icon until recently. I had not changed anything or added any extensions... The only change was the most recent High Sierra OS updates. I can't even remember the last time I added an extension, if any. It just started randomly doing this on its own.

Pkshadow said

If that fails to fix the icon when dragging it out uninstall Firefox and delete the Mozilla Firefox Folders but not your Profile Folder. https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data then reinstall with a Full Version Installer from your source or from : https://www.mozilla.org/firefox/all/

Please do this

Refresh did result in getting the fox icon back. We'll see if it sticks this time. Thanks. My bookmarks did not disappear, although I did back them up beforehand.

Welcome and great. Enjoy

I have the same issue—which has appeared after updating to v.59.02—but after removing the dock icon I went to the Applications folder to drag it over and saw that the icon on Firefox is the same grey box with the "A" described above! Not sure if any of the above steps will work, but thought I'd see if anyone else knows what to do to fix this.

Hanasazi, please read just a few comments above. I am the original poster of this question. Do what pkshadow posted- "Posted 12/24/17, 6:55 PM". "Refresh" worked for me. The Firefox icon has corrected itself and has been fine ever since then.

Thank you, lisaviv. I refreshed Firefox but the icon didn't change. One of the oddities I'm experiencing after the update to 59.02. Guess I'll just have to live with it for now as work calls...

Wow, I was reassured by the Mozilla statement that refreshing would not remove any passwords, but it dumped them all! It also dumped my master password (I'm a web designer and have to protect lots of them) and won't let me set a new one. Time to start a new support request...

Hi, when Hanasazi posts in your question it moves your question to Responded and we do not see your messages. Please let us know what is going on so we can continue helping you. Hanasazi has been asked not to post in others questions.

Hanasazi, can you Please continue in your own thread /questions/1211757 instead of hijacking this thread started by lisaviv. Thank you.

Try to reinstall Firefox.

• /questions/1204656 Icon in the dock looks like a pad and pencils...no fox!