[Lazarus] Keeping a main menu item visible after it's been clicked

[Mark Morgan Lloyd]

Mark Morgan Lloyd wrote:
> If a main menu item contains something like "More detail ↴" which 
> enables additional lines, is it possible to prevent the item closing 
> when that's clicked? I've tried doing this (Linux/gtk2)...

Or put another way: under program control how can a main-menu item be 
made visible, as though it had been clicked?

Any thoughts would be appreciated, I haven't had much success with the 
documentation and archive.

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

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