MouseWithoutBorders does not pass keystrokes to remote machines when Prisma Browser is focused on primary machine

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### Microsoft PowerToys version

2.2.1.0327 (standalone MWB)

### Installation method

WinGet

### Area(s) with issue?

Mouse Without Borders

### Steps to reproduce

I run the standalone build of MouseWithoutBorders (from WinGet) using the physical keyboard and mouse on one primary system and connecting to/controlling two secondary systems.

When I see this problem, I am running with the Palo Alto Networks Prisma Browser

https://www.paloaltonetworks.com/sase/prisma-browser

which is a Chromium fork focused on security and central IT management that will be used by my employer. Unfortunately, while anyone can download and install the application, it looks like you need to log in with an employer-authorized account to run it -- so this may be hard to reproduce.

When I encounter this problem, I am running with the Prisma Browser focused on my primary system. When I move the mouse off the edge of the primary system's displays to control either of the secondary systems, mouse input (movement and clicks) are sent to the secondary system as expected. However, keyboard input is unexpectedly sent to the Prisma Browser application on the primary system.

When any other application, including Firefox, Chrome, or Edge, is running on the primary system, both mouse and keyboard input are sent to the secondary system.

I have no idea if the problem involves MouseWithoutBorders or if the Prisma Browser is intentionally preventing MWB from operating as intended. I could imagine some "security focused" software from having low-level hooks designed to prevent the injection of malicious input from malware that might cause problems with tools like MWB.

### ✔️ Expected Behavior

Keyboard input should always be sent to secondary systems when the mouse is moved off the edge of the primary system's displays.

### ❌ Actual Behavior

Keyboard input is sent to the focused Prisma Browser process when that app has focus on the primary system, even if the mouse has moved off the edge of the primary system's displays.

### Upload Bug Report ZIP-file

_No response_

### Additional Information

Running with Windows 11 25H2 on the primary and both secondary systems.

### Other Software

_No response_

No source files or tests are named. Start by reproducing the issue with the standalone Mouse Without Borders build, Prisma Browser, and a comparison browser, then trace the keyboard-input handling used when control moves to a secondary machine. Done means keyboard input reaches the secondary system without affecting the focused Prisma Browser process.

Written by the indexing model from the issue text.