Hi!

Could you please tell us which theme is causing this issue?

Thanks!

Firefox keeps on reverting to the "Firefox OS" theme (I think that's what it's called)

Can you attach a screenshot?

• http://en.wikipedia.org/wiki/Screenshot
• https://support.mozilla.org/kb/how-do-i-create-screenshot-my-problem

Use a compressed image type like PNG or JPG to save the screenshot.

Does this help?

tom01 wrote: Firefox keeps on reverting to the "Firefox OS" theme (I think that's what it's called)

"Firefox OS" refers to the mobile operating system, developed by Mozilla. https://developer.mozilla.org/en-US/Firefox_OS

Are you using the Default Theme in Add-ons manager -> Appearance or are you trying to use a third-party complete theme or a Personas background image?

The screenshot shows that you use a Persona (lightweight theme) for the toolbar (user interface) area.

Do you mean that this Persona is gone after you have opened the Customize window?

Did you check for issues caused by one of the extensions?

• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

To James: There is a theme called "Firefox OS" with the Firefox OS fox in the theme. I am using a Persona (I think...)

To Cor-el: The theme reverts to the Persona even after I try to change it. See the image below. It states that Firefox is in the default theme, even though it isn't.

Hi!

When you go to customize, the theme will not show but when you exit customization the theme reappears again..

Is this the issue you are currently having? If so, this happens with other themes as well.. If not, please describe your issue the best you can so we can try to reproduce it so we can help you.

Thank you!

I try to change my theme and it works, but when I go to customize my menu it goes back to the "Firefox OS" Persona.

I found the problem! There was an add-on installed (Default theme engine - Personas Interactive 1.6.3.14) that I disabled and now I can change my background as normal!

Thank you all for your support, I really appreciated it!