I got the same issue (or something similar)....
To be sure, I started with a fresh new empty catalog... and imported my day's pictures which were already copied in a local directory(Add to catalog)
A- marking red a few pictures
B- marking yellow a few other pictures.
C- move to Develop section
D- filter by color red
E- do some light adjustment to one picture. seems allright
F- select another picture (app freeze before showing that other picture... waited 10 minutes.. still frozen, force application close by the Window's task manager)
A-Loads the older catalog, I had to reload the newer catalog.
B-Selected one picture (no filter)
C-made some light adjustments to picture
D-selected another picture, this time it seemed fine...
E-Alt-Tab to come to this web page to comment issue
F-Alt-Tab to go back to Lightroom, lightroom is frozen, waited 5 minutes... had to kill app with task manager.
Lightroom is unworkable.....