Visuals: Show Borders button doesn't stay on and works erratically

[CaviaPorcellus]

In the configuration settings, in the Calendar section, there is an option Visuals: Show Borders. If the box is checked and the settings are closed, when returning to the settings it goes back to being unset.

Another issue (maybe this should be separate?) is that it the effect it has on the calendar is erratic.

When turned on dots appear:

When off the dots are gone:

However, that is only how it works with KDE's default panel. When used in Latte Dock, the opposite occurs: the dots appear when the setting is off, and they disappear when the setting is turned on. The effect doesn't seem to persist in Latte Dock either: after a while when the clock is clicked, the dots reappear regardless of what the user set.

Incidentally, I'm not sure why dots appearing can be called "showing borders", so maybe has a very different affect in different themes?

I'm using Better Inline Clock version 3.1 on Kubuntu 21.04 (Plasma 5.21.5) with the default Breeze/Kubuntu theme.