2043569 - Paste context menu missing in Squarespace editing interface

Status: NEW

(Core :: DOM: Copy & Paste and Drag & Drop, defect)

Description

[Jan Brasna [:janbrasna]]

Attachment: Screenshot 2026-05-28 at 18.08.22.png

It seems the whole context menu is not in "editing mode" (i.e. missing Undo, Redo, Emoji & Symbols, Writing Direction etc. for me), according to the original reporter being a recent regression.

Confirmed on a Mac, original report is from Windows.

Created a free trial using https://www.squarespace.com/templates/altaloma-fluid-demo (restmail should work), chose an existing static page like "About" there, went into "Edit". The editing UI is writable, I can paste with CMD+V, I have my menubar item Edit › Paste available, active, and working. Just context menu directly for the editing element where the caret is looks like for a readonly element, not contenteditable.

(Other simple reference contenteditable and pasteboard demos as on MDN work as expected.)

Comment 1

[Jan Brasna [:janbrasna]]

There are reports for v151 also for eBay and LinkedIn:

• https://support.mozilla.org/questions/1583888
• https://support.mozilla.org/questions/1584172

that appear the same? I'd have treated each as an individual webcompat issue, but the timing of all seems suspicious.

Comment 2

[Jan Brasna [:janbrasna]]

Got a few spotty results but this one seems plausible:

Tested mozilla-central build: 2026-04-17 (verdict: b)
Tested mozilla-central build: 2026-04-16 (verdict: g)
Narrowed integration regression window from [dca1688c, 7f96aadf] (3 builds) to [dca1688c, 22fffa2c] (2 builds)
Tested autoland build: ca24cef5 (verdict: g)
Tested autoland build: bb732fbb (verdict: g)
Tested autoland build: 55116109 (verdict: b)

https://hg-edge.mozilla.org/mozilla-central/rev/551161093ac62a253604afcf21977f4ecbb6f5cc

Will try the builds again later to see if I end up on the same bug 1470017 regressor.

Comment 3

[Jan Brasna [:janbrasna]]

Since this seems to cease reproducing at some point in early 153 builds I'm assuming this has the same root cause as bug 2041720 and got fixed with bug 2033243 hopefully?

Looking for the bugfix, I'm in the neighborhood:

Tested mozilla-central build: 2026-05-08 (verdict: g)
Tested mozilla-central build: 2026-04-29 (verdict: b)
Tested mozilla-central build: 2026-05-04 (verdict: g)
Tested mozilla-central build: 2026-05-02 (verdict: b)
Tested mozilla-central build: 2026-05-03 (verdict: g)
Tested mozilla-central build: b21b5804 (verdict: g)
Tested autoland build: 166e11c0 (verdict: b)
Tested autoland build: b92005ef (verdict: b)
Tested autoland build: 8df15f3c (verdict: g)
Tested autoland build: 7ddf5e1c (verdict: g)
Tested autoland build: 52d25a41 (verdict: b)

e.g. somewhere around https://hg-edge.mozilla.org/integration/autoland/rev/c4e1cacf12f4ebe31834cdd778ab1411edca1513 plausible?

Some parts of the bug 2033243 stack might be fixing this.

I don't feel confident setting dependencies or duping it straight away — feel free to do so if you're seeing the same bisection as above.

(LinkedIn new post interface is also affected if that's easier to reproduce for someone, see one of the linked sumo threads for reference.)

Comment 4

[BugBot [:suhaib / :marco/ :calixte]]

Set release status flags based on info from the regressing bug 1470017

:emilio, since you are the author of the regressor, bug 1470017, could you take a look? Also, could you set the severity field?

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