Why can encoding go wrong in Angular templates in Visual Studio?

Question

Angular

There is an app.component.html file in the project, it has Cyrillic.
If you close the project and open it again, then the encoding in it for some reason flies to 1251. More precisely, the encoding remains, but the contents of the file are re-encoded into krakozyabry. You have to convert to UTF-8.
The problem is with all the files that are in the Angular application folder.
With all other files containing Cyrillic and located one level higher, there are no such problems.
Already opened it through Notepad ++ and manually set the encoding - it does not help.
Tried deleting the file and re-creating it.
Can anyone come across?