Feature request - Cooling fan speed-up time
This feature will really help on machines that have larger fans and/or longer ducts. It takes a moment to get the cooling fan up to speed and for the airflow to reach its target. I had a job recently with bridges where the cooling only kicked in after the bridge was printed. I ended up using OrcaSlicer which has this feature, which allows you to set a time for the airflow to get going, and it made the print possible.
RE: Feature request - Cooling fan speed-up time
3DPC this is a user to user forum. Feature requests, bug reports etc need to be made at the appropriate github repository. For Prusa slicer that is located here https://github.com/prusa3d/PrusaSlicer/issues , for Mk3 printers that is here https://github.com/prusa3d/Prusa-Firmware/issues and for buddy based printers such as the mini, the mk4 and the Xl that is here https://github.com/prusa3d/Prusa-Firmware-Buddy/issues
Before opening new issues though please search both open and closed issues using as many keywords as you can think of as there are already MANY issues and far too many people open duplicates.
For your request there is already https://github.com/prusa3d/PrusaSlicer/issues/10004 which is a duplicate of https://github.com/prusa3d/PrusaSlicer/issues/3590 for example.
The orca slicer feature you mention was ported from Super Slicer which unfortunately seems to be a dead project now and not under active development.