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### Problem description
<!-- Describe the bug that you fixed/feature request that you
implemented, or link to an existing issue describing it -->
When entering for the end value the same value as the start it is not
recorgnized as valid region, because end must be strictly greater than
begin. Due to the +1 in the Region constructor this is not correct,
because the end is included in the range.
### Implementation description
<!-- Explain what you did to correct the problem -->
### Screenshots
<!-- If your change is visual, take a screenshot showing it. Ideally,
make before/after sceenshots -->
After:
### Additional things
<!-- Anything else you would like to say -->
### Problem description
#### Problem 1
In borderless mode ImHex disables the standard macOS titlebar rendering
and input processing. As a result double clicking the titlebar does not
trigger the native macOS behavior set in `System Settings -> Desktop &
Dock -> Double-click a window's title bar to [Zoom/Minimize/Do
nothing]`.
#### Problem 2
The ImHex window shows up as blank/transparent when de-minimizing it
from the dock.
#### Problem 3
Widgets experience ghost hover inputs from the past position of the
cursor during live resizing.
### Implementation description
ImGui elements consume input events in the order they are drawn. As a
result by "drawing" an `InvisibleButton` over the content area of the
titlebar we can catch unprocessed clicks in the titlebar area.
Connecting this button's double clicks to the native window is then a
trivial endeavour.
The blank windows was caused by the rendering stack clearing the GL
buffer, but proceeding to draw nothing in it. I have short circuited
this path.
Ghost hover inputs were squelched by consistently moving the ImGui
cursor to `0, 0` during a live resize. The OS will dispatch a cursor
positioning event once the resizing ends, restoring normal behavior.
### Screenshots
N/A
### Additional things
N/A
---------
Co-authored-by: Nik <werwolv98@gmail.com>
