In case you don’t know, Chromium-based Edge is the new Default PDF Reader in Windows 10 now, the browser already offers basic PDF Viewer functions, today Microsoft added Text highlighting feature to new Microsoft Edge browser in Canary and is enabled by default.

Classic Microsoft Edge offers way many functions to manage PDFs in the browser such as read-aloud, add notes, allows to set Page View in a single or two-page layout, highlight text and more.
For a PDF opened in Chromium Edge, Microsoft allows the user to perform these things: Zoon in/out of contents, Rotate PDF in clockwise/counterclockwise direction, draw and erase, print and save modified PDF locally to your computer.
Now you can highlight text, one of the PDF features that exist in old Edge and lacks in the new Edge browser, for that.
1. Ensure you’re using the latest Microsoft Edge Canary 80.0.340.0 or later, load any PDF,
2. Select a portion of text with your mouse, right-click and in the “Highlight” menu choose any color from Yellow, Green, Light blue and Pink.

To highlight text with a different color or to undo the created highlighting,
Right-click on the highlighted text in PDF > Highlights, choose another color from the available or select “None”.
The feature is enabled by default and can be controlled with “Enable text highlights for PDF” flag available in edge://flags page. The flag offers this description: “Enables creation and modification of Text Highlights for PDF” on Mac and Windows.

This post was helpful. Earlier I did not have the option to highlight in different colors but now after enabling it in edge flags (as mentioned above) I am able to highlight text in different colors. Thanks