acarbonart wrote:
Mojave 10.14.5
It remains on the jpg icon when viewing through the finder. Something it didn't struggle to do yesterday. The only difference now and yesterday is that my mac must have updated automatically to this new update.
Have you rebooted since your update— advised.
From where you are now try relaunching the Finder. >Force Quit>Finder>Relaunch.
Try a SafeBoot https://support.apple.com/en-us/HT201262
Takes noticeable longer to get to the login screen, does a 5-15 minute disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, etc. You can log in and test. Reboot and test.