Hey there, are you by any chance subscribed to a lot of communities? If so, that may be the reason for the stuttering when opening the drawer.
This is a known issue and I have fix for that in this PR which should greatly improve that: https://github.com/thunder-app/thunder/pull/1452
Occasionally, it also stutters when I scroll through my feed.
Do you mind sharing if you have full height images enabled? Generally, having that on is a bit more intensive because Thunder needs to calculate the width/height for each image (as Lemmy does not provide that info directly) - this should improve once Lemmy sends back the image dimensions in their API!
If you don’t have that option enabled, feel free to submit a new issue on GitHub and I can take a closer look at it. Thanks!