In inspector, Line Visible has no effect on trill line.
Currently if you want an accidental on a trill you must insert a trill line. Accidentals do not work with the trill from Articulations & Ornaments. When there are multiple parts with accidentals on trills such as this
it would be much easier to be able to make the trill lines invisible that to edit each line so it is short enough to not have a line on it. If you decide to extract parts it is necessary to repeat this process on every part.
In the inspector there is a Line Visible check box as an option that has no effect. It would be nice to be able to have the default be checked and removing the check causing the line to become invisible. This would allow the hiding of several trill lines at once.
Comments
An unfortunate regression, but luckily it's on-screen glitch only. See #271236: "Line visible" property not honored on screen for text lines.
The trill line is not a regression, it also happened in version 2.1. A trill line is not a text line. You can't edit the line properties like a text line, pedal, volta... It just has the same inspector properties as the other lines and can be adjusted (e.g. press ctrl+e to edit it) like other lines.
Asking for this feature has been on my mental list of things to check into and I've been working on that list today.
Sorry, you're right, my mistake.