Preview app text markup not working on M1 Mac mini with Tahoe 26.0.1

Have you tried rebooting? Safe mode?

Start up your Mac in safe mode - Apple Support

Markup in Preview on 26.0.1 is working normally for me (except for the darker text selection color that is a known bug).

Itchentest wrote:

Marking up text in a PDF (highlighting, strikethrough etc) doesn't work since upgrading to Tahoe 26.0.1 on a M1 Mac Mini. Preview version 11.0. All I get a is blue box around the text section which vanishes when I take my finger off the mouse.

[Re-Titled by Moderator]

Original Title: Preview app problems

"Blue box" this sounds like an Accessibility setting...(?)

Change Accessibility settings on Mac

Try a different PDFeditor and compare your results.

a true PDF editor, there are many, here are a few examples:

Acrobat Reader / Adobe Acrobat DC

https://get.adobe.com/reader/

PDFpen / Nitro

https://pdfpen.com/pdfpen/

pdfExpert

https://pdfexpert.com/

Master PDF Editor

https://code-industry.net/get-masterpdfeditor/

PDFgear

https://www.pdfgear.com

further—

Call Customer Support (800) MY–APPLE (800–692–7753)

or on line https://getsupport.apple.com/

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Contact Apple Support - Apple Support

Itchentest wrote:

Thanks for the reply, yes I know about other PDF editors, it's why Preview doesn't work all of a sudden that perplexed me.

To be proactive you can file a bug report / submit your Apple Feedback here:  Product Feedback - Apple

The current stable release of Tahoe  including bug fixes,  security updates  is your macOS 26.0.1