May I ask how to change the theme of HeiDiSQL

How to switch between internal themes？

In Tools > Preferences > General > "Style theme".

Note that the "Windows" theme is the default one.

Hey! Anyone knows how to change the selection color, it's almost unreadable. And remove these white borders on top/left sides? Thanks

You can't change these colors on the users side. You could use a different style which does not have these issues.

All the custom themes has this issue. Pretty sad, wanted to use the dark theme. Maybe it can be patched somehow with the resource editor to change the font color at least?

Not so here. You're probably using an outdated HeidiSQL version. Current version looks ok (with the Material style):

Thanks, no it's the latest one, but probably my OS w7 is a bit dated and doesn't support some features. But I think I found how to get rid of the borders and probably change the highlighting color by playing with GetSystemColor. Not a delphi dev myself, but will try it out.

https://medium.com/@vuio/delphi-borderless-form-a2538e3ec48

https://stackoverflow.com/questions/38023579/resize-form-even-if-it-is-borderless-remove-bevel-edge

https://theroadtodelphi.com/category/vcl-styles/

I just fixed your links above, maybe that helps :)

I suppose you are aware that Windows 7 is insecure due to its stopped support? You probably have bigger issues than these system colors...

Thanks, it didn't let me post the links.

I suppose you are aware that Windows 7 is insecure due to its stopped support?

I'm sure it's pretty secure, the core stack hasn't changed that much since Vista times. It has all the recent ESU patches and the firewall+router both are well configured, the files are checked with virustotal. In 25 yrs I catched the virus only once when the sourceforge was compromised (2010 or so) and the file was too large and containerized.

I see it's a bit complicated issue, probably the vsf skin file should be also modified. Will try.