Frequent hang time on Mac --infinite pinwheel: Readability files?

I’ve been cleaning up/organizing some old files that I saved with the Readability app (and imported into a DT database) but I’m experiencing severe hang time (must Force Quit from DT) when I try to access/open them now. Since Readability is no longer available (retired/sunset), could that be causing the issue and is there a way to modify to files to allow access? Sometimes the file does show up in preview, but most of the time it’s just black. Thanks for any suggestions!

Could you please launch Apple’s Activity Monitor application (see Applications > Utilities), choose the frozen DEVONthink 3 in the list of processes, select the menu item View > Sample Process and send the result to cgrunenberg - at - Thanks in advance!