The idea is simple: with one click, users could activate a temporary annotation layer over the current webpage and draw directly over it without modifying the webpage itself.

The tool could include:

Pen / freehand drawing
Highlighter
Arrows
Circles and rectangles
Text
Eraser
Undo / Redo
Adjustable line thickness
A few customizable colors
Clear all annotations
Screenshot with annotations

Why would this be useful?

Opera GX already brings many tools and services into the browser, reducing the need to switch between different applications. A built-in annotation layer would take that philosophy one step further.

This would be particularly useful for teachers, students, presenters, trainers, tutors and anyone who regularly explains information on screen.

For example, a teacher could open a dictionary, article, PDF, website or educational resource and activate Annotation Mode. They could then underline a word, circle an important part, draw an arrow, add a short note or highlight a sentence directly on the screen.

This would eliminate the need to open another application such as Paint, PowerPoint or a dedicated annotation tool. It would also be useful when presenting content on a projector, interactive display or TV.

A possible workflow:

Open webpage → Click Annotate → Draw/highlight/explain → Take screenshot or exit → Continue browsing

I think this would fit Opera GX particularly well because the browser already focuses on bringing useful tools directly into the browsing experience instead of making users rely on separate applications.

It could also become useful beyond education: presentations, tutorials, technical support, online meetings, demonstrations and collaborative browsing are other potential use cases.

The feature doesn't need to be a full digital whiteboard. A simple, lightweight overlay that works on top of any webpage would already provide significant value.

In short: turn any webpage into a temporary annotation canvas with one click.