Shotcut Not Accepting Some Time Values

I’m editing my first video and running into a problem when entering a time value to move to a position in a track. It accepts most values but I often will enter a value and Shotcut will bump the value up or down and will not accept the exact time I want to enter. If I try using the up / down arrow keys, Shotcut will skip over the value I want to enter. It may also skip over a small range of values. It’s like there is a gap in the track or timing information. Does someone know what would cause that and how to fix ??

You may be working with 29.97 fps video and dealing with drop-frame timecode:

And another article on the subject:

Shotcut denotes drop-frame with a semi-colon instead of regular colon as the last separator in the time value field.