QuickLook.Plugin.StickyPosition

A QuickLook plugin that remembers where you put the preview window, per file type, and opens it there every time, with no jump.

Why: QuickLook opens every preview in the middle of the screen, so a preview you keep beside your work has to be dragged back there every time you press Space.

Made with Claude.

Install

1. Download QuickLook.Plugin.StickyPosition.qlplugin from the latest release.
2. Select it in Explorer and press Space to preview it with QuickLook.
3. Click Install, then restart QuickLook.

Use

• Remember a position: drag or resize a preview. It's saved for that file type when you let go. Drag a .pdf preview once, and every .pdf opens in that spot at that size; Markdown, images and folders each keep their own spot.
• Lock a position: open the ⋯ menu on a preview and choose Lock position for .pdf. The window's current position is saved, and later drags and resizes of .pdf previews move only that window; the next .pdf still opens at the locked spot. Unlock position for .pdf goes back to saving every drag.
• Forget a position: ⋯ menu, Forget position for .pdf. This also unlocks the type. The next .pdf opens where QuickLook puts it.
• Pinned windows: dragging a pinned ("prevent closing") preview doesn't save anything. A new preview that would open exactly on top of another preview window is shifted down and right a little.

File types you haven't placed yet open wherever QuickLook puts them, as if the plugin weren't installed. Dragging, snapping, maximising and fullscreen all behave normally. Previews with a fixed size (folders, unknown files, the plugin installer) keep their size; only their position is remembered.

Several monitors and scaling

Positions are stored as fractions of the monitor's work area, so they survive resolution and scaling changes. With several monitors, the preview opens on the monitor QuickLook chose (the one with the window you pressed Space in), at the saved spot on that monitor.

A default position for new file types

Settings live in QuickLook.Plugin.StickyPosition.config, in QuickLook's data folder (%APPDATA%\pooi.moe\QuickLook\, or the equivalent under %LOCALAPPDATA%\Packages\...\LocalCache\Roaming\ for the Microsoft Store version). Each Pos_<type> value is left,top,width,height as fractions of the work area; Lock_<type> is 1 for a locked type. To give unplaced types a default position (here, a tall column on the right), exit QuickLook first, then add:

<DefaultPosition>0.545,0.03,0.42,0.92</DefaultPosition>

Why the window never jumps

QuickLook works out the window's position before it shows it, and the plugin changes that position at that moment, by rewriting WM_WINDOWPOSCHANGING on the viewer window. So the window is never drawn anywhere else first. Plugins that move the window afterwards always show a visible jump. Only QuickLook's own placement of a newly opened file is changed.

Build

No .NET SDK needed. build.ps1 compiles with the C# compiler that ships with the .NET Framework, against the QuickLook.Common.dll of your installed QuickLook, and writes dist\QuickLook.Plugin.StickyPosition.qlplugin.

.\build.ps1                              # Microsoft Store QuickLook
.\build.ps1 -QuickLookDir D:\QuickLook   # portable QuickLook
.\build.ps1 -Install                     # also copy it into the plugin folder

Testing placement

scripts\ checks placement in a running Store QuickLook without touching the keyboard or mouse:

• preview-steps.ps1 opens and closes previews on a chosen monitor and prints or captures the window. It puts a magenta window behind the preview to make that monitor active, so expect it to flash. Windows won't hand it focus while you're typing; it stops and says so.
• build-debug.ps1 installs a build that logs every placement message to Public\Documents\sp-debug.log. -Restore puts the normal build back. Both restart QuickLook.

.\scripts\preview-steps.ps1 -Steps 'm2,t:C:\notes\a.md,tree,cap:C:\temp\a.png,c'

Caveats

• The plugin reads QuickLook internals by reflection: ViewWindowManager._viewerWindow, ViewerWindow._path, ViewerWindow.Pinned and ViewerWindow.ContextObject. A QuickLook release that renames the first two switches the plugin off: previews go back to QuickLook's usual placement, and one line in QuickLook's log says so. Tested on QuickLook 4.5.0; the names were still present in QuickLook's source on 2026-09-14.
• A position set with Win+Arrow isn't saved on its own; drag the window, or use Lock position.

Credits

The idea of reaching QuickLook's viewer window by reflection comes from QuickLook.Plugin.EnhancedPreview by ChouDan6 (GPL-3.0). This plugin places the window with a different technique.

Licence

GPL-3.0, the same as QuickLook. See LICENSE.