Not without editing the sidebar.php I don’t think.
No, there’s no sidebar hooks. Not built in to WordPress itself.
Why not?
Shouldnt there be?
How can i add content to the sidebar without having it as a widget and not editing theme files?
Because a lot of themes i have exists in newer versions but i dont want to upgrade because i have edited the sidebar.php now. And it takes some time doing that with 100 themes.
any other solution for me? plugin or something in mu-plugins folder?
Not really. Header and Footer are required elements. Sidebar is not. I have themes without one, or with my widgets all over the place.
You know if you make a Child Theme, then you can edit your theme AND be able to upgrade the master theme 🙂