Issue

Unless some WriteConsoleW() call happens between two ReadConsoleInputW() calls, using SetConsoleMode() to set/clear the ENABLE_MOUSE_INPUT mode flag doesn't take effect.

• This is a regression in Terminal 1.18.1462.0.
• The problem does not exist in Terminal 1.17.11461.0.

Repro steps

The repo includes a pre-built code-signed copy of the Repro.exe executable.

1. Start Windows Terminal 1.18
2. Run the Repro.exe program from this repo
3. Move the mouse over the terminal window; you should see no output
4. Click the primary mouse button on the terminal window; you should see no output
5. Hold Ctrl+Alt and move the mouse or click the mouse button

EXPECTED:

• You should see output acknowledging that ReadConsoleInputW received mouse input records.

ACTUAL:

• Terminal 1.18 -- there is not output (incorrect behavior).
• Terminal 1.17 -- the output reports received mouse input records (correct behavior).

Observe the impact of WriteConsoleW()

If in step 2 you instead run Repro.exe --verbose then the program prints verbose output acknowleding when Ctrl+Alt are pressed or released and indicating the new console mode being used.

The additional verbose output line eliminates the repro, and makes the ENABLE_MOUSE_INPUT change properly affect the WaitForSingleObject(in, INFINITE) call.

So, in Terminal 1.18, unless some WriteConsoleW() call happens between two ReadConsoleInputW() calls, using SetConsoleMode() to set/clear ENABLE_MOUSE_INPUT doesn't take effect.