Can you say more specifically what you're trying to do? There has been not functional change in what you can edit, though obviously the layout has changed significantly.
I noticed the tips in the preview pane of the selected attachment, which indicates adding notes to attachment is no longer supported. The users can edit this note attached to the PDF files only if the corresponding notes have been transferred to the separate item note. Now, therefore, what if I want to associate some comments with a certain PDF?
As shown in the above screenshot, the note for Contents used to be editable in Zotero6, however, it read only in Zotero7beta. I used the area above the Contents to annotate the corresponding PDF attachments, but now I can't implement it anymore.
Ah, got it, sorry. Yes, that message means what it says — embedded notes on attachments are no longer supported, so you need to convert the note to a sibling child note if you want to edit it. These embedded notes already had awkward limitations in Zotero 6 — not supporting embedded images — for technical reasons. But this feature never made that much sense, since for most people the vast majority of items only have one primary file, and even for items with supplementary materials as additional attachments, they're all conceptually representing a single parent item, so just creating child notes of that item seems appropriate. And now that there's a built-in reader with annotations (including note annotations), you can always add annotations directly to the PDF/EPUB/webpage as a replacement if you really want to.
The main use of embedded attachment notes was always table-of-contents feature from ZotFile, but there would be better ways to replace that functionality than this weird type of note.
Thanks for your detailed comment, it is helpful for me. Additionally, I have realized that there are two separate names for attachments in Zotero7beta, and the attachment title (at the top of the screenshot) can contain additional info, my primal problem can be effectively resolved as a result.
After I make the annotations a standalone note, is there any way to make the new item a sub-item to the PDF, or at least for the relationship between the two to be automatically created? At the moment if I migrate all to standalone notes, I'm going to have thousands more items, and I need to manually make a relation between the new note and the existing PDF.
@ainmean-aite: Yes, you can add the PDF as a related item. Select a note and click the + button to the right of "0 Related" at the bottom of the editor pane.
(Or you can create a parent item and put both the attachment and the note under it. Whatever style of organization works better for you.)
https://s3.amazonaws.com/zotero.org/images/forums/u7294073/240i81dunwg3sh5pd3sm.png
As shown in the above screenshot, the note for Contents used to be editable in Zotero6, however, it read only in Zotero7beta. I used the area above the Contents to annotate the corresponding PDF attachments, but now I can't implement it anymore.
The main use of embedded attachment notes was always table-of-contents feature from ZotFile, but there would be better ways to replace that functionality than this weird type of note.
(Or you can create a parent item and put both the attachment and the note under it. Whatever style of organization works better for you.)