Sets markup
as the contents of the tooltip, which is marked up with Pango markup.
This function will take care of setting the [[email protected]:has-tooltip] as a side effect, and of the default handler for the [
[email protected]:GtkWidget:query-tooltip
] signal.
See also [[email protected]_markup].
this |
a `GtkWidget` |
markup |
the contents of the tooltip for this |