Can you upload a screenshot?

Does it still happen in Troubleshoot Mode?

Delete,

I'll try again. This - https://snipboard.io/D3yTPB.jpg - is close to real life size.

What is the native resolution of the monitor setup? Also is this default FF setup - no scripts or Addon? And is this URL font issue only Gmail or other sites as well?

It is the menu font size, not the website contents. Last week's update resulted in a smaller font size.

The display resolution: 2560 x 1600. This is Firefox without scripts or Add-ons. Are there Add-ons that increase the Firefox menu font size?

I captured an image ... https://snipboard.io/hRo3ye.jpg ... but the image resolution is not as clear as the actual resolution. Using Microsoft Word, the Firefox menu font size is Arial Narrow 9.

The links listed in the initial post indicates others with the same problem.

Does it still happen with the ESR version (115)?

You can look at this thread:

• /questions/1384204 Since the last update, the Firefox screen does not fit my system setting(125%)

If setting browser.display.os-zoom-behavior = 0 doesn't work for you then you can create a new Number pref in about:config and set its value to 100. Paste ui.textScaleFactor in the search bar and select the Number radio button and click the '+' button to add the new Number pref, enter the value (100) and click the blue OK button to confirm.

• about:config => ui.textScaleFactor = 100

You can open about:config via the location/address bar. On the warning page, click "Accept the Risk and Continue" to open about:config.

• https://support.mozilla.org/en-US/kb/about-config-editor-firefox

Thanks zeroknight and cor-el.

I did enter about:config, etc. None of them changed anything.

The Mozilla / Firefox code writers could make this easier by adding Tools > Settings > Language and Appearance > Menu Font Size. There would be no risk. This would help a lot of people!

You can set layout.css.devPixelsPerPx to 1.0 (default is -1) in about:config. Adjust its value in 0.1 or 0.05 steps like 1.1 to enlarge or 0.9 to reduce until icons/text looks right. You may need values above 2.0 if you have a high resolution display but make sure not to use values too large or too small.

• modifying layout.css.devPixelsPerPx affects user interface and webpages (global zoom)

Firefox has a Zoom section in Settings to set the default zoom level for webpages.

• Settings -> General -> Language and Appearance -> Zoom

You can open about:config via the location/address bar. On the warning page, click "Accept the Risk and Continue" to open about:config.

• https://support.mozilla.org/en-US/kb/about-config-editor-firefox

The sequence --- about:config > yes to risk > layout.css.devPixelsPerPx > next line, edit [pencil icon] > 1.5 > save icon does work.

I had not realized I need to select the pencil icon on the next line.

Unfortunately, it also makes the spacing larger and icons larger ... not desired.

Is there a way to request this change? --- Mozilla / Firefox code writers, Add Tools > Settings > Language and Appearance > Menu Font Size.

Thanks!