Do not show hours if the video is less than 1hr
Should not be possible to delete/edit ":" and "." separators
Input field has to show the entire number, without scrolling as today
When you enter one item, for example hours - we should automatically focus(and select) the next item (To demo this, open the design and type values starting from the 1st field)
Should be possible to paste text in correct format:
If hours exist: "nn:nn:nn:nnn"
If there are no hours: "nn:nn:nnn"
Handle errors in that way so users know which field has the error. Update error after you focus next field. Example ("Incorrect format: hours" or "Incorrect format: minutes, milliseconds")
Note: you should start typing values from the 1st field