Import of ZAP proxy is terribly slow or even stuck

[ciapatakoza]

Description:
The import from ZAP proxy is terribly slow or even hangs burp. No matter how much cores or ram assigned to VM.

Steps To Reproduce:
Generate the ZAP history for ~1600 requests/responses including binary blobs. The final file exported by ZAP was ~224MB.
Try to import that file in logger++, it will make entire burp unresponsive. Already waiting 40min to end import but this probably will not happen. There is no logs or exceptions in console. Just 100% use of the core all time.

Expected behavior:
Import file with any size within 5-10min. Show any kind of progress in console?

Screenshots:

Version:
3.20.0