Cursor snaps to left edge when taskbar auto-hide is enabled (StuckRects3 Right boundary = 0 after SpaceDesk loads)
Hello SpaceDesk Team,
I am reporting a reproducible issue with SpaceDesk on Windows 11 involving the taskbar auto-hide feature and pointer behavior. After SpaceDesk activates an iPad as a secondary display, Windows begins forcibly snapping the mouse cursor to the leftmost pixel of the primary monitor whenever the auto-hidden taskbar appears.
This behavior does not occur before SpaceDesk is started.
This report includes a full geometry dump from the Windows StuckRects3 registry block, which confirms that SpaceDesk is injecting invalid monitor boundary data into Windows’ display topology.
Environment:
Windows 11 Pro:
Edition Windows 11 Pro
Version 25H2
Installed on 8/23/2025
OS build 26200.8875
Serial number [redacted]
Experience Windows Feature Experience Pack 1000.26100.334.0
SpaceDesk:
Driver version 2.2.22.0, downloaded 2026 06 14, installed same date
Viewer version 0.0.41.0, downloaded 2026 06 14, installed same date
Primary display: standard DPI monitor
Secondary display: iPad connected via SpaceDesk via USB link, placement is to lower left of primary display
Taskbar set to auto-hide
Mixed-DPI configuration
Issue Summary
When SpaceDesk initializes the virtual display for the iPad, Windows begins forcibly repositioning the mouse cursor to the leftmost pixel of the taskbar whenever the hidden taskbar appears. This behavior does not occur before SpaceDesk is started.
Observed Behavior
Cursor jumps to X=0 on the primary monitor when the auto-hidden taskbar is revealed. Behavior begins immediately after SpaceDesk activates the virtual display. Behavior stops when SpaceDesk is not running.
Technical Assessment
After SpaceDesk activates the iPad display, the Windows StuckRects3 geometry block becomes corrupted. Specifically, the Right boundary of the taskbar rectangle is set to 0, producing a negative-width bounding region. This causes Windows to clamp the cursor to the minimum X coordinate (0) when revealing the auto-hidden taskbar. This is consistent with a virtual-display driver incorrectly rewriting the primary monitor’s bounding rectangle.
Diagnostic Data (PowerShell Dump)
Code
=== StuckRects3 Geometry Dump ===
Raw Hex Bytes:
30 00 00 00 FE FF FF FF 03 00 00 00 03 00 00 00
60 00 00 00 30 00 00 00 00 00 00 00 08 04 00 00
80 07 00 00 38 04 00 00 60 00 00 00 01 00 00 00
Decoded Values:
Taskbar Position Byte (8): 3
Auto-Hide Flag Byte (12): 3
Bounding Rectangle:
Left: 96
Top: 48
Right: 0
Bottom: 1032
Critical Finding: The Right boundary = 0 is invalid. This produces a negative-width rectangle. Windows clamps the cursor to X=0 when revealing the auto-hidden taskbar. This corruption occurs only when SpaceDesk is active.
Reproduction Steps
- Start Windows 11 with taskbar auto-hide enabled.
- Verify cursor does not snap to the left edge.
- Launch SpaceDesk and connect the iPad as a second display.
- Move the cursor to the bottom edge to reveal the hidden taskbar.
- Cursor snaps to the leftmost pixel of the taskbar.
Expected Behavior
- Cursor should remain at the user’s pointer location when the hidden taskbar appears.
Actual Behavior
- Cursor is forcibly repositioned to the left boundary of the taskbar region.
Please advise whether this is a known issue and whether additional diagnostic data would be helpful. I can provide full registry dumps, display layout information, or additional geometry captures if needed.
Cursor snaps to left edge when taskbar auto-hide is enabled (StuckRects3 Right boundary = 0 after SpaceDesk loads)
Hello SpaceDesk Team,
I am reporting a reproducible issue with SpaceDesk on Windows 11 involving the taskbar auto-hide feature and pointer behavior. After SpaceDesk activates an iPad as a secondary display, Windows begins forcibly snapping the mouse cursor to the leftmost pixel of the primary monitor whenever the auto-hidden taskbar appears.
This behavior does not occur before SpaceDesk is started.
This report includes a full geometry dump from the Windows StuckRects3 registry block, which confirms that SpaceDesk is injecting invalid monitor boundary data into Windows’ display topology.
Environment:
Windows 11 Pro:
Edition Windows 11 Pro
Version 25H2
Installed on 8/23/2025
OS build 26200.8875
Serial number [redacted]
Experience Windows Feature Experience Pack 1000.26100.334.0
SpaceDesk:
Driver version 2.2.22.0, downloaded 2026 06 14, installed same date
Viewer version 0.0.41.0, downloaded 2026 06 14, installed same date
Primary display: standard DPI monitor
Secondary display: iPad connected via SpaceDesk via USB link, placement is to lower left of primary display
Taskbar set to auto-hide
Mixed-DPI configuration
Issue Summary
When SpaceDesk initializes the virtual display for the iPad, Windows begins forcibly repositioning the mouse cursor to the leftmost pixel of the taskbar whenever the hidden taskbar appears. This behavior does not occur before SpaceDesk is started.
Observed Behavior
Cursor jumps to X=0 on the primary monitor when the auto-hidden taskbar is revealed. Behavior begins immediately after SpaceDesk activates the virtual display. Behavior stops when SpaceDesk is not running.
Technical Assessment
After SpaceDesk activates the iPad display, the Windows StuckRects3 geometry block becomes corrupted. Specifically, the Right boundary of the taskbar rectangle is set to 0, producing a negative-width bounding region. This causes Windows to clamp the cursor to the minimum X coordinate (0) when revealing the auto-hidden taskbar. This is consistent with a virtual-display driver incorrectly rewriting the primary monitor’s bounding rectangle.
Diagnostic Data (PowerShell Dump)
Code
=== StuckRects3 Geometry Dump ===
Raw Hex Bytes:
30 00 00 00 FE FF FF FF 03 00 00 00 03 00 00 00
60 00 00 00 30 00 00 00 00 00 00 00 08 04 00 00
80 07 00 00 38 04 00 00 60 00 00 00 01 00 00 00
Decoded Values:
Taskbar Position Byte (8): 3
Auto-Hide Flag Byte (12): 3
Bounding Rectangle:
Left: 96
Top: 48
Right: 0
Bottom: 1032
Critical Finding: The Right boundary = 0 is invalid. This produces a negative-width rectangle. Windows clamps the cursor to X=0 when revealing the auto-hidden taskbar. This corruption occurs only when SpaceDesk is active.
Reproduction Steps
- Start Windows 11 with taskbar auto-hide enabled.
- Verify cursor does not snap to the left edge.
- Launch SpaceDesk and connect the iPad as a second display.
- Move the cursor to the bottom edge to reveal the hidden taskbar.
- Cursor snaps to the leftmost pixel of the taskbar.
Expected Behavior
- Cursor should remain at the user’s pointer location when the hidden taskbar appears.
Actual Behavior
- Cursor is forcibly repositioned to the left boundary of the taskbar region.
Please advise whether this is a known issue and whether additional diagnostic data would be helpful. I can provide full registry dumps, display layout information, or additional geometry captures if needed.
