Automatic mosaic
Find automatic mosaic in its submenu, detect private content, add or remove coverage, link matching items, adjust areas, and check the final result.
Before sharing a chat or document screenshot, automatic mosaic can detect avatars, contact details, and other content and process private information. Check each location afterward to cover missed parts or remove unnecessary coverage.
Find automatic mosaic in the submenu
In the default layout, “Auto Mosaic” is in the “Mosaic” submenu. Click the small angled arrow to the right of the mosaic tool, then select “Auto Mosaic.”
For a screenshot, select an area first. On an image pin, press SpaceSpace to show the annotation toolbar. You can also use the default shortcut Shift+[⇧ Shift+[: hold Shift and press the left bracket key.
The entry moves if you customize the toolbar layout. For frequent use, move it to the top level with “Adjust” at the bottom right of the menu. See Manage button order and levels.
Review the automatic result first
Selecting the tool detects content in the current image area without requiring you to draw each box. When detection finishes, actionable areas are marked briefly.
“Automatically process privacy mosaic” in “Annotation” → “Auto Mosaic” settings is on by default. Detected phone numbers, email addresses, IP addresses, URLs, nicknames, and avatars are processed automatically, as are QR codes detected in screenshots. Add ordinary text, general numbers, and other targets as needed.
This setting applies after you enter automatic mosaic and detection finishes; it does not automatically redact every screenshot. With it off, detection still runs, but you choose what to cover.
Click to add or remove coverage
Blue boxes are detection hints and do not mean the content is already covered. After the hints end, hover over a target and use its color to see what clicking will do.
- Blue: detection hintAvatars are processed; ordinary digits remain. Blue is not coverage.
- Red: click to addHover over unprocessed digits, then click to cover.
- Green: click to removeHover over the same processed target and click to reveal it.
Hover inside the content to process, away from its edges. A red highlight means clicking will add mosaic.
Hover over a processed target to see a green highlight. Clicking removes this target's coverage and reveals the original content.
Keep checking other locations. If you make a mistake, press Ctrl+Z⌘ Command+Z to undo the last addition, removal, or area adjustment.
Process matching content together
“Synchronous operation” in the style bar is checked by default. Clicking one target adds or removes coverage for a group detected as the same content, such as repeated instances of a nickname or avatar.
It does not process every avatar or all text together. Check the highlighted area before clicking. Uncheck “Synchronous operation” to change only this occurrence. If some targets in a matching group are already covered, clicking the green highlight removes coverage for that group.
Select several targets or correct a detected area
- Match identical contentMatching nicknames highlight together; clicking green removes both.
- Select a batchThe red box intersects two rows; release to cover both.
- Resize one targetWait for the resize cursor at the edge, then drag to change only this target.
Hold the left mouse button outside target edges and drag to select multiple detected targets intersecting the rectangle. Releasing the mouse performs an action based on its color:
| Box color | Result on release |
|---|---|
| Red | Adds coverage to targets that are not yet processed |
| Green | All targets in the box are processed; removes their coverage |
| Blue | No detected targets selected; makes no change |
This selection processes detected targets. It does not fill the whole dragged rectangle with mosaic, and “Synchronous operation” does not extend it to matching content outside the box.
If a target covers only part of some text, hover over its edge or corner until the resize cursor appears, then drag outward and release to apply. Resizing affects only this occurrence.
For content that was not detected, switch to ordinary Mosaic and add coverage with a rectangle or pencil.
Choose an effect and check before sharing
“Mosaic mode” at the far left of the style bar offers “Mosaic” and “Blur.” Drag the slider to the right for larger pixel blocks or stronger blur. Each mode remembers its own strength. Changes here affect all enabled automatic mosaic areas in the current image.
Switching tools hides the colored hints but preserves the processed result. Return to automatic mosaic to add or remove coverage or change areas.
Set the screenshot selection before adjusting detection results when possible. Changing the selection runs detection again, so check again afterward. Before copying or saving, confirm all content to hide is covered, especially text ends and undetected areas.
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