Checking on Version 81.0.402.0 (Official build) canary (64-bit)
Favorites set to icon-only are no longer reverting back, they are keeping their icon-only status but their status is not synced, i.e the same favorite on other devices are not becoming icon-only.
Read Aloud option is removed on PDFs altogether. previously it was available but greyed out.
i also should mention that there haven't been any new flags added to Edge canary since Version 81.0.396.0 (i.e since last week). i have the list of flags of that version and comparing to current Version 81.0.402.0, there is no change.