spacebar Install

Quick Look Plugins On Sequoia

Why old .qlgenerator plugins stopped working in macOS 15, and what replaces them

  • macOS 15 Sequoia and later
  • Sources linked below
.qlgenerator pluginIn ~/Library/QuickLook. Not loaded since macOS 15.
Quick Look extensionShips inside an app, switched on in System Settings.
What changed in macOS 15 Sequoia. Diagram drawn in HTML.
queue.ts
Try it: a TypeScript file, the kind old plugins handled, in spacebar’s own preview page, running in your browser.

Quick Look add-ons such as QLColorCode and QLStephen were .qlgenerator plugins. Apple replaced them with app extensions, and in macOS 15 Sequoia the plugins stopped loading: one that worked on Sonoma does nothing now.

What Apple says

The macOS Sequoia 15 release notes, under Quick Look › Deprecations: “Support for deprecated Quick Look Generator plugins is being removed. To provide previews and thumbnails for your custom file types, migrate to Quick Look Preview Extension and Thumbnail Extension API.”

They stopped in macOS 15.0: Howard Oakley wrote for The Eclectic Light Company on 31 October 2024 that “QuickLook Generator plugins no longer work”, and Michael Tsai’s blog quoted him on 5 November 2024.

Check What You Have

  1. ls ~/Library/QuickLook /Library/QuickLookOld plugins. These no longer load; you can move them to the Trash.
  2. qlmanage -m pluginsWhat loads. On our macOS 15.4.1 Mac, only Apple’s own.
  3. pluginkit -mA -p com.apple.quicklook.previewExtensions. + on, - off, no mark for the default.

The same list is in System Settings › General › Login Items & Extensions › Quick Look.

Replacements That Still Work

Each is an app extension, so it works on Sequoia. Keep one previewer per file type.

If you usedForTry
QLColorCodeSource code, highlightedSyntax Highlight (free, open source) or spacebar
QLStephenText files with no extension, such as READMEspacebar or Syntax Highlight; both take Space for text files with no extension. See a QLStephen alternative
A Markdown plugin.md files, renderedQLMarkdown (free, open source) or spacebar
A JSON pluginJSON, formattedspacebar, or Syntax Highlight for highlighted source

QLColorCode’s README still says to install it by dragging it into ~/Library/QuickLook, and QLStephen has an open issue, from 16 October 2025, asking for an app-extension rebuild. Both checked on GitHub on 2 October 2026.

Where spacebar Fits

spacebar is a free, open-source Quick Look extension for macOS 13 and later. An extension can’t claim everything a plugin could.

What spacebar Opens

  • Markdown and folders, with the folder in a sidebar
  • Code and config
  • Archives
  • Files with no extension

What Apple Keeps

  • Text and HTML
  • CSV and PDFs
  • Images, audio and video

The optional Space helper opens those in spacebar’s window too. Compare Quick Look apps.

Questions

Can I turn .qlgenerator plugins back on in Sequoia?

Apple documents no way to. Its release notes say to move to preview and thumbnail extensions, so the fix is an app that ships one.

Does qlmanage -r bring an old plugin back?

No. On Sequoia, Quick Look’s list of previewers leaves out third-party plugins. It can help when an extension doesn’t show up after you install or update it.

Why does my new Quick Look extension do nothing?

Check it’s ticked in System Settings › General › Login Items & Extensions › Quick Look, and that no other extension claims the type. Opening the app once usually registers its extension.

Install It

Download for Mac

Or paste this in Terminal

curl -fsSL https://spacebar.patebryant.com/install.sh | sh

The script downloads the latest notarized release from GitHub, checks its SHA-256 and installs to ~/Applications, no sudo. Read the script.

Sources

Fetched on 2 October 2026: