Comment nodes don't have a `closest` method so when passing one to
`closestElement`, the method crashed.
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Step to reproduce in website:
- Go to debug mode and to website app
- Click on configuration > websites
- Select a website and in the `custom_code_footer` field add an HTML
comment
- Go to the website and try to enter edit mode -> Crash
The same error will be visible if you simply enter edit mode and drag &
drop the "Code" snippet and enter an HTML comment inside it.
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Step to reproduce in marketing automation:
- Install marketing automation
- Click on a campaign > Add a new activity
- On the mail template field, type something > Create and edit
- Select plain text -> `element.closest is not a function`
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task-3083797
opw-3081323
opw-3081278
closesodoo/odoo#107486
X-original-commit: 3a9177dd6a6f12f75d0df8146b692e3486f2467c
Signed-off-by: David Monjoie (dmo) <dmo@odoo.com>