I've been looking into this for you since you mentioned the issue in a previous question. I've now found out where you set it, but only you can really know what you need to set.

• Settings > General
• scroll to bottom
• click on 'Config Editor' button
• In search type: zoom
• look for : toolkit.zoomManager.zoomValues
• By default it has these values: .3,.5,.67,.8,.9,1,1.1,1.2,1.33,1.5,1.7,2,2.4,3,4,5

The numbers I've made bold are the ones that used when you use Ctrl++ or 'Zoom' > 'Zoom In' So when you use Ctrl++, you can click on it up to 10 times - increments using 10 stages because there are 10 higher number options. The number 1 is the default reset zoom setting starting point.

• To Edit click on the pencil icon button

This allows to manually alter the numbers. I tried the following: .3,.5,.67,.8,.9,1,2.5,5,7 After the number 1, I only entered 3 numbers: 2.5 and 5 and 7 Note: use a comma to separate numbers. This had the following effect. When I now use Ctrl++, it increments to a larger zoom quicker and I can only use the Ctrl++ a total of 3 times because there are only 3 numbers after the number 1. Basically less clicking/pressing of keys. There is less choice in the number of variable zoom levels. But if you find yourself doing a lot in Ctrl++ to get to a size you want then this fix will help a lot.

It means you need to consider what numbers you need after the number 1 As this is a personal adjustment setting, you may need to fiddle about with the numbers until you get what you prefer.

• To save your choices click on the tick icon.

If you ever need to reset back to the default set of numbers then you can click on the far right curved anti-clockwise arrow.

Remember - Before you test your settings Reset everything back to default: View > Zoom > Reset Zoom and you may discover you need to reselect email as well.

Thank you, Toad-Hall!

This is getting closer.

But unfortunately it still does not change the default zoom level, i.e. the level from which the zooming starts. The starting level is still way too small. ... Yes, I could set the value after the 1 to my desired level and would a least only have to zoom in once at each startup. ... But a) this would still be annoying and b) the fine-tuning gets lost and I could not zoom out a bit in case needed.

So I hoped, that Thunderbird would start in the middle of that row of numbers and if I increased them all, it would start higher ... but no, it always starts with a 1 (even if it is the first in the row) ... and goes from there.

-(

The default setting for all font size in Message Pane is done in 'Settings' > 'General' which I answered in the other question you asked. I advised choosing a suitable size if you need to see a larger size font on all occasions - aka currently you have to zoom for every email.

I had no idea what settings you were using so I suggested:

• Fonts for Latin and Other Writing Systems
• Set 'Proportional Size' to eg: 18
• Set 'Monospace Size' to 18
• Set minimum size to 16 (allows a bit smaller but stops smaller font size)

But you felt this was too large.

So if you want the default setting to increase but the above settings were too much then try a bit less:

• Fonts for Latin and Other Writing Systems
• Set 'Proportional Size' to eg: 14
• Set 'Monospace Size' to 14
• Set minimum size to 12 (allows a bit smaller but stops smaller font size)

But 'zoom' itself is entirely different. It is a manual setting on a per email basis which is initiated only when you select it. If you find you sometimes use zoom, but not always then the method mentioned above means you can preset the zoom levels meaning you don't need to keep clicking to get a suitable level.

But the zoom level number 1 means using default starting point to be whatever you set up in 'Settings' > 'General' > 'Language & Appearance' section > 'Advanced'

Yes, I have to zoom in *every* email. They are *all* too small.

But your suggested method with the font-sizes leads to unreadable results. ... NOT because the font is too large, but because the space between the lines is too small. And also still only 1/3 of the available space is used and 2/3 is wasted.

Please look at the screenshot. The font is exactly the *right* size, but the message is not readable anymore.