Remove "Hidden Preview" on iMessages on iMac
I suddenly have several folks with whom I text regularly start to have "Hidden Preview" on iMessage. I have searched how to undo "Hidden Preview" and the hourglass image but to no avail. All answers seem to be for iPhone. iPhone says show Preview so . . what to do? The message is not shown, the recipient has not received the message and the message is not on my computer in some hidden place (that I could find). What's going on here??? SOMEONE, pls help. This is new (2 days) and I need it to stop. Is this a hack? Are my text messages safe?Thank you for any real answer.
iMac 27″, macOS 10.15