Created attachment 157147 [details]
Sample document (originally from bdo#125444, alas in ODP format now)

When editing the sample document, and specifically editing the chart on the
sole slide, in the "Elements" tab of the "Properties" pane there are two 
checkboxes labeled "Title" and "Subtitle".

Checking each of these adds a "Title" and "Subtitle", respectively, to the
chart.

Alas un-checking them again, both the "Title" and the "Subtitle" remain in
the chart, which is not the expected behavior in case of a checkbox.


Note 1: For the checkbox related to the "Legend", the behavior is as expected:
the legend appears and disappears as the checkbox is toggled.

Note 2: Originally observed with a PPTX document, but exactly reproduces when
saved as ODP, so attaching an ODP testcase.