How to Use the Highlighter Tool in Screenshots Without Obscuring Text
Highlighting text or UI elements should guide the eye, not turn your screenshot into a messy finger-painting. Here is how clean visual highlighting works.
Feature Live in GoFully v1.1.2
The new Multiply-Blend Highlighter with smart horizontal snap is officially available in GoFully v1.1.2. You can now highlight code snippets, paragraphs, and key metrics with zero text occlusion right inside your browser. See our full journey on the public roadmap.
The Problem: Why Most Screenshot Highlighters Look Cluttered
Most browser capture tools implement highlighters as standard canvas paint brushes with a simple alpha channel (e.g. 50% yellow opacity). This causes two major defects:
1. Washed-Out Text Contrast
Standard alpha blending places yellow pigments over dark letters, turning crisp 100% black typography into muddy grayish-brown.
2. Crooked Freehand Strokes
Freehand mouse drawing produces wavy, uneven lines that look unpolished in professional executive presentations and customer support docs.
The GoFully Approach: Multiply Blend & Horizontal Snap
Inspired by macOS-native tools like CleanShot X, GoFully v1.1.2 integrates two dedicated rendering features:
Canvas globalCompositeOperation = 'multiply'
Instead of painting over text, multiply blending darkens the background with the highlighter pigment while leaving underlying black text pitch black. Your letters remain razor-sharp.
Hold Shift for Level Horizontal Ruler Snapping
Holding Shift locks the highlighter angle to a perfectly straight horizontal line, matching the exact baseline of text paragraphs and data tables.
Step-by-Step: Highlighting Screenshots in v1.1.2
Step 1: Capture the Page
Take a full-page or visible area screenshot using GoFully. The image opens immediately in the annotation viewer.
Step 2: Select the Highlighter (H)
Click the highlighter icon on the top canvas toolbar or press the H key.
Step 3: Choose Color & Stroke Thickness
Select from curated palettes: Canary Yellow, Emerald Green, Electric Cyan, or Soft Rose. Adjust stroke width to match your typography size.
Step 4: Draw with Straight-Line Snapping
Click and drag across the sentence. Hold Shift to lock the line horizontally.
Complementary Annotation Guides
Learn how to combine highlighting with privacy redaction and full-page scrolling captures:
Related Guides & Tutorials
How to Draw on Any Live Website and Capture It with Your Marks
Use GoFully's Draw on Page to sketch arrows, highlight text and add sticky notes right on a live website, then capture the visible area or the full page with your marks in place.
How to Capture a Single Element on a Webpage (Card, Table or Chat Message)
Capture just one card, table, chart or chat message in Chrome.
How to Auto-Redact Emails, Card Numbers and API Keys in Screenshots
GoFully's Auto-redact reads your screenshot on your device and covers emails, card numbers, phone numbers, ID numbers, IP addresses and API keys with black boxes you review before export.
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