Mail composer and reading window slows down to a crawl with 1000+ people in people folder

[pamen]

Replying to emails causes an up to a minute delay when people folder is full (I have 1076 contacts in there at this point).

8GB RAM, real hardware (lenovo x201 2 cores i5) system is very fast in general, no resource issues, no running task issues, reboot or update does not solve the issue.both beta2 and nightly builds from 09/Apr/2021 have the problem.

Working with email app becomes impossible. Once people are deleted / moved - no issues with speed. People are all in one folder, no subfolders. browsing people with tracker is , as usual, very smooth and fast.