Red letter "A" appears in top left corner
I got this red letter "A" in the upper left corner in some websites. No idea what it is and I want to get rid of it once and for all. Hope someone can help. Thanks!
Chosen solution
Can you list the installed extensions?
If it works in Safe Mode and in normal mode with all extensions (Firefox menu button/Tools > Add-ons > Extensions) disabled then try to find which extension is causing it by enabling one extension at a time until the problem reappears.
Close and restart Firefox after each change via *"3-bar" menu button > Exit (Power button)
- Windows: File > Exit
- Mac: Firefox > Quit Firefox
- Linux: File > Quit
All Replies (9)
Start Firefox in Safe Mode to check if one of the extensions (Firefox menu button/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.
- Switch to the DEFAULT theme: Firefox menu button/Tools > Add-ons > Appearance
- Do NOT click the Reset button on the Safe Mode start window
- https://support.mozilla.org/kb/Safe+Mode
- https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes
Did you check your security software?
Thank you, Cor-el, for your reply. I did restart Firefox in Safe Mode and the red letter disappeared. What should I do next? Will I need to start Firefox in safe mode each time, or is there something else that I need to do?
I don't know if I have any security software. This is a brand new Mac laptop and I'm not sure what security software there is installed, if any.
That shield looks familiar, but I can't place it.
If you hover your mouse over it and look for a "tooltip" or link, or right-click it, or click it, does that uncover any information about what it's doing there?
Chosen Solution
Can you list the installed extensions?
If it works in Safe Mode and in normal mode with all extensions (Firefox menu button/Tools > Add-ons > Extensions) disabled then try to find which extension is causing it by enabling one extension at a time until the problem reappears.
Close and restart Firefox after each change via *"3-bar" menu button > Exit (Power button)
- Windows: File > Exit
- Mac: Firefox > Quit Firefox
- Linux: File > Quit
Are you using the Flash Control extension? https://addons.mozilla.org/en-US/firefox/addon/flash-control/
These are the extensions I've installed in order to block the ads. I have suspected that one of them might be the cause of this pesky thing but I wasn't sure which one and I don't know how to check which one it is. :-(
On my older laptop I used to have only Adblock and it worked well. On this one it didn't want to work properly, so I installed whatever I could find to block the ads.
the-edmeister said
Are you using the Flash Control extension? https://addons.mozilla.org/en-US/firefox/addon/flash-control/
Yes, I have that one. Do you think it's the one that causes that red shield to show up?
cor-el said
If it works in Safe Mode and in normal mode with all extensions (Firefox menu button/Tools > Add-ons > Extensions) disabled then try to find which extension is causing it by enabling one extension at a time until the problem reappears. Close and restart Firefox after each change via *"3-bar" menu button > Exit (Power button)
- Windows: File > Exit
- Mac: Firefox > Quit Firefox
- Linux: File > Quit
I just tried that with the Flash Control and it seems to be the one.
Thanks so much everyone for your help! You guys rock! :-)
jscher2000 said
That shield looks familiar, but I can't place it. If you hover your mouse over it and look for a "tooltip" or link, or right-click it, or click it, does that uncover any information about what it's doing there?
It is similar to the HTML5 logo, but this specific button is not related to HTML5.