The 'Light' or 'Dark' mode on a computer is very specific and it's a 'Theme' which is why it is located under 'Addons and Themes'. It has nothing to do with 'Language' and 'Appearance' is about font and colour and size - it has nothing to do with Themes.

Please note it is possible to download a Theme, so that means it's an addon hence why they are in same location. It's not going to change because a generic Theme is not the same as choosing how you prefer to alter the appearance of the contents when using the selected theme.

re :but can't find a solution to switch to a readable light version.

I suggest you offer more information on your real issue and see if a good solution can be found that suits you.

Please tell me what OS you are using because the 'System Theme' on Thunderbird will be dependent upon what settings you have on computer. For example: Windows OS has a settings for customised app mode which is dark or light. Windows OS - Settings > Personalisation > Colours will also effect eg: Task bar, button background colours and the thin strip colour which depicts what eg: Quick Filter optins are set.

So if computer has apps mode set to Light then the 'System Theme' setting in Thunderbird will also be Light.

Please offer info about what you are finding difficult to 'read' and perhaps post an image to help explain the problem.

I came here for the first time because I could not remember how to set dark/light. Saw that there was already an answer. A snotty, condescending answer, but an answer. Think I'll keep my failing memories to myself if this is the typical help rendered.

I came here for the first time because I could not remember how to set dark/light. Saw that there was already an answer. A snotty, condescending answer, but an answer. Think I'll keep my failing memories to myself if this is the typical help rendered.

There was nothing snotty or condescending about that comment. It was pure facts. This might be your first time on the support forum but it does not mean you can be rude to others who offer their time freely to help other users. As a heads up, your comment in someone elses question posts emails to that person and anyone following the question.

The person who asked the question just wondered why the setting was not under Settings in appearance. That is a reasonable assumption to make, but the issue was all about themes and they are kept in a separate location. There is nothing wrong with stating that fact because that is just what it is. I offered to help further if the person needed it as there are many potential fixes when it comes to specific user readibility issues. As they did not respond any further, it would seem they were ok. If the information helped you then that's ok too.

Shoot, now you gone and hurt my feelings.