I just updated to the latest Hubitat version 2.3.4.122. I had the same issue on .120 as well. I'm trying to create a Holiday light rule that triggers at sunset and midnight. The sunset works fine. But when I try to set a specific time, I get an error.
Unexpected Error
An unexpected error has occurred trying to load the app. Check Logs for more information.
Error: Unparseable date: "00:01:00"
It looks like this is an issue with Chrome. When using Firefox, it works. I noticed Chrome lets you select seconds where Firefox only lets you select hours and minutes.
Yes, I tired a couple of different times and it seems it doesn't matter what is entered in. I tried a few times to recreate from scratch. The screenshots I sent previously were both new rules configured today since you asked for screenshots.
I'm no longer looking for a fix, as I have it working using Firefox. I just wanted to follow up fyi...