Environment

Windows build number: 10.0.18362.0
Windows Terminal version (if applicable): built from master @ f4294b1

Any other software? N/A

Steps to reproduce

1. Turn off the Windows setting scroll inactive window when I hover over them
2. Have terminal on monitor with scaling other than 100%
3. Have enough text to scroll
4. Focus terminal and scroll with mouse wheel

Expected behavior

Terminal should scroll

Actual behavior

Scrolling behavior is different depending on the mouse position. In some areas, it scrolls properly. In other regions, scrolling won't work.

• If scaling is 100%, then scrolling works properly. If scroll inactive window setting is on, then scrolling works properly.
• Same issue for both normal and non client window

Heres what I think is happening:

With scroll inactive window off, the wm_mousewheel messages are only be sent to current focused window (If i've read the docs correctly).
I think that the window that takes focus is not scaled properly so in some areas the mouse is 'outside' and won't receive the mouse wheel messages (maybe it needs to be focused and hovered?).
Terminal does have a couple windows (the host and the xaml island ones) but i'm not sure which one takes focus when terminal is active. I tried checking for wm_mousewheel in the window procs but I could not see the message being sent.
I have my suspicions that it's the top level window that is supposed to be receiving the messages because using Spy++, when I highlighted the top level window, its size also matched the area where scrolling works. But visually, everything seems to be scaled properly so I'm not too sure now.