Which button? Which OS and widgetset?
Works fine on WIndows for TButton, TSpeedButton, TBitBtn and TRadioButton.
Which button - not just buttons, all controls
Lazarus - Built on GTK
OS - Debian Linux
GUI - KDE 5
When I restart Lazarus and open a form in the IDE, selecting a control, going to an event in the property editor, and double clicking the event to bring it up works properly once, ie the event procedure shows up and
the cursor is placed in it.
After that any such clicking only brings up the procedure without placing the cursor in it.
Sometimes it highlights some tokens in the code for no obvious reason.