Continuity Markup not working correctly
I'm trying to annotate a file on my iPad Pro M2 using my Apple Pencil while reading from the same file on my iMac M1. I'm then using Continuity Markup, as described in this page (Use iPad or iPhone to sketch in or mark up Mac documents - Apple Support). However, when I get to Step 2 of the directions for Continuity Markup, I simply do not have that annotate button. Instead, I have this:
On the other side, I can correctly annotate the same file when I start from preview or directly from an attachment in email message.
Why is Continuity not working correctly?
iMac 24″, macOS 13.0