Outline every element to instantly debug layout and spacing - depth tinting, hover inspector, one-click selector copy.
Users
10K
0 in 30 days
Rating
4.5 / 5
unchanged in 30 days
Ratings
17
0 in 30 days
Store rank
#8,912
#7,621 among extensions
Version
3.2
updated 29 Jul 2026
Users
monthly, 3 years
Latest, 15 Oct 2026:10,000 usersMove the mouse over the chart for any month
Ratings count
monthly, 3 years
Latest, 15 Oct 2026:17 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About Outliner CSS
Outliner CSS: Your Perfect Debugging Tool
Outline every element to instantly debug layout and spacing, depth tinting, per-site memory, one-click selector copy.
Key Features:
- One-click outlines in five colours
- Depth tinting to visualise nesting
- Hover to inspect, click to copy the selector
- Alt+Shift+O toggles the current page
- Your colour preferences sync, nothing about the sites you visit is ever stored
- No trackers, no external requests
What's new in 3.1
- Depth tinting fixed (silently broken in 3.0)
- DOM structure mode rebuilt: dashed context outlines, solid hover highlight, click-to-copy selectors
- New: keyboard shortcut and synced colour preferences
- Redesigned popup with automatic dark mode
- No site-access permissions and no stored site records: acts only when you invoke it, remembers only your colours
Lightweight by design: one injected stylesheet-style sweep, no trackers, no analytics, no external requests.