Steps to demonstrate:

1. Launch AOO Writer
2. choose menu 'Insert > Frame', select "Macro" tab
   Notice that for a moment:
   - mouse pointer changes the look from "Normal Select" to "Busy".
   - label "Existing macros" is displayed.
   
   Once the content of "Macros" list is shown, label disappears and
   mouse pointer reverts to "Normal Select".

3. In list "Macros" select module.
   If that module contains any macro, label "Existing macros"
   appears on screen for good.


Compare this behaviour (and layout) with dialog invoked via
'Tools > Macros > Organize Macros > OpenOffice Basic':

- no "iterim" label displayed before due content is shown;
  label "Existing macros in:" is displayed all the time, even if
  given module has no macros.
- both labels i.e. "Macro from" and "Existing macros in:" are
  vertically aligned
- vertical spacing between labels and their respective lists is greater 
  (and optically more pleasant) than spacing for label "Macros"
  in "Frame" dialog.


Relevant screenshots are in the attached files:
"1. Frame dialog" and "2. Comparison".

Short video demonstrating the case of "Frame" dialog is available
at the following link:

https://drive.google.com/file/d/1MVzuUsI35HpJHjSux9WsUiPxFXT2q1OI/view?usp=sharing


NOTE:

1. It seems to be a general bug for assigning macro.
   Observable in AOO Writer not only in Frame dialog, but also in:
   Picture, Hyperlink, ImageMap Editor and AutoText.
   
   ( Screenshots for the above cases are in the attached file:
     "3. Other cases" )
 
   It also occurs in other AOO component

2. The same holds true for AOO 4.1.7