After a post is clicked, it seems that all thumbnails are forced to refresh. (Attached image shown immediately after a click)
Also, what may just be the result of a cache clear, doom scrolling seems to cause a similar lag after scrolling past +50 posts. Thumbnail loading becomes laggy, but not sure if related to the issue above.
When the lag starts, Connect will lag fairly bad for as long as a minute. I have also turned off image preload, but that had no effect.
Side bug, changing the title in the new post edit cleared my first post body.
Not looking for an alternative. This issue came from active development and I am running a beta.
Just check some of the recent posts and the dev is still here.