Adjust the reference angle of the 2D rotation stabilizer When using the rotation stabilizer of a movie clip, we select 2 markers on the horizon e.g. and the angle will get adjusted to keep this line horizontal. Fine.

But now, let's say that my 2 reference points are not horizontal but draw a diagonal in the footage (one on the top right, one of the bottom left). How can I apply a sort of angle-offset to the rotation stabilizer so that I end up with my footage straight and not 45 degree!

Of course we could apply a rotation afterward but we would loose some serious quality needlessly.

An approach I thought about was to move the entire track of one of the markers so that it is at the Y level of the other, but in the graph we cannot select only one axis (unless we select the thousands of points one by one...) "a" will select both X and Y. A way to do that would have been to use the offset since the beginning of the tracking, but it took me an entire day to build my markers tracks mostly manually so I can't start all over now.

Thank you!
Ok I answer my own question :)

The reference angle of the rotation stabilizer is based on the angle of the points at frame 0 of the footage, regardless of the Start/End of the project. This angle will be the reference to maintain for the rest of the footage.

Therefore, to adjust the offset angle of the stabilizer, simply put the marker used for rotation at a different location at frame 0 only, then keep the rest of the track and go observe the results in the middle of your footage.