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Still trying to enlarge the font and, if possible, change the font in the toolbar and tabs, how do I do this?

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I have had this issue for some time. Not long ago I remedied it by adding Theme Font & Size changer. However, that is no longer usable with Quantum. I switched my browser to Waterfox, as I could then access this add-on, using an older version. Today, I find that this has been disabled as well. I still have the issue of needing the font & size of the toolbar and tabs bigger and bolder and would like to be able to change the actual font as well. How can I do this? I need the font & size to be bigger due to my eye problems. I use the computer a lot and this is becoming a major issue for me.

I have had this issue for some time. Not long ago I remedied it by adding Theme Font & Size changer. However, that is no longer usable with Quantum. I switched my browser to Waterfox, as I could then access this add-on, using an older version. Today, I find that this has been disabled as well. I still have the issue of needing the font & size of the toolbar and tabs bigger and bolder and would like to be able to change the actual font as well. How can I do this? I need the font & size to be bigger due to my eye problems. I use the computer a lot and this is becoming a major issue for me.

Chosen solution

Hi SUNSHINE47, the first thing to try editing is Firefox global scaling factor. By default, Firefox follows your Windows "Text Size" setting. On laptops, that's often 125%. On desktop systems, it may be 100%. But Firefox also lets you override this and specify your own scaling factor.

This will scale up both the text and the icons. Here's how to give it a try:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful or accepting the risk.

(2) In the search box above the list, type or paste devp and pause while the list is filtered

(3) Double-click the layout.css.devPixelsPerPx preference and enter 1.5 and click OK. This is equivalent to setting the "Text Size" in Windows 10 to 150% (assuming you can still do that in Windows 10).

What do you think, is this the same, better, too large? You can experiment with this setting, but I suggest not making it smaller than 1 and not making it larger than 3.

If things get out of control, you can right-click the setting and choose Reset, which is the bottom item on the right-click context menu.

Can you find a size that works well overall?

(If not, the next step -- and to change the font face you'll also need this -- would be custom style rules in a userChrome.css file. I'll have to research that a bit.)

Let us know how you make out.

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Modified by Shadow110

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Seçilmiş Həll

Hi SUNSHINE47, the first thing to try editing is Firefox global scaling factor. By default, Firefox follows your Windows "Text Size" setting. On laptops, that's often 125%. On desktop systems, it may be 100%. But Firefox also lets you override this and specify your own scaling factor.

This will scale up both the text and the icons. Here's how to give it a try:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful or accepting the risk.

(2) In the search box above the list, type or paste devp and pause while the list is filtered

(3) Double-click the layout.css.devPixelsPerPx preference and enter 1.5 and click OK. This is equivalent to setting the "Text Size" in Windows 10 to 150% (assuming you can still do that in Windows 10).

What do you think, is this the same, better, too large? You can experiment with this setting, but I suggest not making it smaller than 1 and not making it larger than 3.

If things get out of control, you can right-click the setting and choose Reset, which is the bottom item on the right-click context menu.

Can you find a size that works well overall?

(If not, the next step -- and to change the font face you'll also need this -- would be custom style rules in a userChrome.css file. I'll have to research that a bit.)

Let us know how you make out.