I've noticed a significant increase in loading time/enabling of the Map Series in Layout Properties in Pro projects as more layouts/maps are added to a project. For a fresh project this loads almost instantly, but for larger projects this is increased to several minutes (I've waited 20mins before). Is this a known issue for larger projects? Or perhaps there is a work-around out there?
What version of ArcGIS Pro are you using? In 2.8 upgrades were made to help address this problem. If you are using an earlier version I recommend updating.
This is a really frustrating issue. I'm using Pro 3.0.2 and I've just reached 15 minutes in trying to open the map series properties in the layout properties window.
That's not good. It shouldn't take that long to open a properties window.
Unfortunately, without more information about your specific project and machine setup I can't tell you if this is a bug or if something else is going on. For this case I'd recommend reaching out to technical support. They can do more advanced troubleshooting, hopefully fixing the issue. And if there is a bug they can get it to the right team to fix.