We found an issue in cfreport when where a font being referenced within the report was an old font no longer included in current Window OS.   We had just moved from server 2019 to server 2022, and the CF from 2018 to 2021.  After reports of horribly slow performance on a particular report, we did all kinds of investigation to figure out why… we were eventually able to determine that there was a font referenced in the report that was no longer pre-loaded in the current OS.  We removed it, clicked save and immediately the report began running full speed. Check all the fonts referenced.   The issue we had was with ArialUnicode and @ArialUnicode.   – Rich Toomsen