"new cell" below or above not rendered properly in Safari and duck duck go

## Description

using safari and duckduckgo in macOS (15.0), the button or shortcut key to add a new cell above or below does not result a new cell being added/rendered.

## Reproduce

click on "+" or `esc` + `b` or `c`, in safari or duckduckgo browser, nothing happens, sometimes even refresh does not reveal the new cell..

## Expected behavior

## Context

OS = macOS 15.0 on M1
Safari = Version 18.0 (20619.1.26.31.6)
duckduckGo = Version 1.99.0 (234)
python = 3.12
jupyter nb = Version: 7.2.2

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