Magnus says that one reason we're using read-only html inputs in the summary dialog is to allow selecting the text and copying it with right-click, etc. There should be a way to do this with divs using contemporary CSS, which is how we're doing it for email messages (subject, etc.) in the 3-pane mail view.
Bug 1631902 Comment 25 Edit History
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Magnus says that one reason we're using read-only html inputs in the summary dialog is to allow selecting the text and copying it with right-click, etc. There should be a way to do this with divs using contemporary CSS, which is how we're doing it for email messages (subject, etc.) in the 3-pane mail view. Edit: see https://searchfox.org/comm-central/source/mail/themes/shared/mail/messageHeader.css#341-345