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Font size on the browser itself (not the pages it shows)

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With the upgrade to FF 89, the font used to display text on the browser itself (not the webpages it displays) has changed to be a thinner and possibly smaller font. My eyes do not like this!

I need to be able to either make it bold, or make it larger, or possibly both. I have tried changing the font in the settings page, but that seems to only apply to webpages, which is not what i need.

I'm running win 10 on a Toshiba Satellite laptop and Firefox v.89.

Thank you for any suggestions.

Ivy

With the upgrade to FF 89, the font used to display text on the browser itself (not the webpages it displays) has changed to be a thinner and possibly smaller font. My eyes do not like this! I need to be able to either make it bold, or make it larger, or possibly both. I have tried changing the font in the settings page, but that seems to only apply to webpages, which is not what i need. I'm running win 10 on a Toshiba Satellite laptop and Firefox v.89. Thank you for any suggestions. Ivy

Chosen solution

Just for reference, what is the default font size?

Read this answer in context 👍 0

All Replies (10)

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There is a an "advanced preference" which you can change. In a new tab enter about:config in the url bar, accept the risk and find this setting: layout.css.devPixelsPerPx The default value is -1.0. You could try changing that in increments of .5. A value of 1.0 may suit you. If that doesn't help, you can use a file called userChrome.css which you would create with a text editor. Are you willing to do that?

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Thanks TerryN21. I tried a range of values from -3.0 to 2.0 and it just got smaller, with the smallest being at 2.0, and -3.0 not being any larger or smaller. I did restart the browser between each setting.

Is there any negative implication to using userChrome.css? If not, I'm not averse to trying that.

Ivy

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I don't know of any negative implication. I have been using a userChrome file for 15+ years. https://www.userchrome.org/how-create-userchrome-css.html

I have the following code to increase fonts in the browser itself. The marks /* */ around the first line indicate that line is comment, not code.

/* global font */
* {
  font-size: 13pt !important;
}

Modified by Terry

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Hi TerryN21,

What do I do with the file once I've created it?

Thanks, Ivy

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Oh, never mind, TerryN21 - I just noticed the link you posted!

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By the way, the forum modified that code, it should be:

TerryN21 said

I don't know of any negative implication. I have been using a userChrome file for 15+ years. https://www.userchrome.org/how-create-userchrome-css.html I have the following code to increase fonts in the browser itself. The marks /* */ around the first line indicate that line is comment, not code.
/* global font */
* {
  font-size: 13pt !important;
}
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Chosen Solution

Just for reference, what is the default font size?

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Thanks All! That userChrome file worked!

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never mind - found it - OK, now that that's improved, I don't suppose you can tell me how to do the same for all of the apps I'm running?? :-))

Modified by ifasko

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gyaltnnh said

Just for reference, what is the default font size?

On Windows, tabs use the Segoe UI font at 12 pixels (3/4 of the default size used for web pages, which is 16 pixels). I don't know about Mac/Linux.