As presented in https://discuss.pixls.us/t/alignment-over-planetary-captures/30103, I tried to use the OpenCV's matchTemplate() to propose an alternative algorithm on planetary alignments.
This short "proof-of-concept" patch is working quite decently on a few SER files I got, but it obviously needs more work to be fixed (eg. I didn't tested all sensor configuration) and maybe optimized, if you guys think that this is valuable enough for Siril.