my thunderbird client 115.18.0 (64-bit) is very sluggish with Reagan.Com Mail but seems to work much faster with gmail and proton.

When I highlight multiple messages for deletion; it can take up to a minute to respond; when I am working with gmail or proton, the deletion is immediate. When I am accessing Reagan with browser, the multiple deletions are also immediate. Appears to definitely be a handoff issue. Suggestions? I use Thunderbird on 2 win11 os and 2 linix mint 2.1 machines. I only delete and store to local on one machine (win11) ver/build 23H2: 22631.6199.