Locking keyframes from moving and editing?

Hello.

I was hoping if you could give me some advice.
When i’m working on an animation in timeline editor, i like to focus on different parts of animation on different times.
However on more than one occasion, while editing keyframe positions (select all), i accidentally ended up moving keyframes for a part of animation that i have already finished.

Is there a way to select specific keyframes and simply lock them from being moved or edited?

Thank you in advance.

Hmm… you can lock channels? I don’t think there’s a way to lock a selection of keyframes, could be good add-on territory