[DUG] WIndows 10 Oddity - Icon disappears from Taskbar

[John Bird]

I have a program built under D2007, I recently added the line to the DPR 
file

Application.MainFormOnTaskbar := True;    //V3.15.12.3

And since then at unpredictable times the icon will disappear from the 
taskbar.  I think have seen same on Windows 7.

Task manager or pressing Alt+Tab shows its running, but not on task bar, and 
on giving it focus the icon re-appears.
I looked for code hiding the main form, and didn't find any - there is some 
code to do Application.Minimize.

I am surmising its one of:

-The main form is pretty small
-D2007 doesn't get this right

Anyone have any ideas?