Does overflow-wrap work in Apple Mail?

overflow-wrap is partly supported in Apple Mail. Closest to Proton Mail: Apple Mail, which agrees on 203 of the 300 features both are tested on.

overflow-wrap in Proton Mail

Partial overflow-wrap is partly supported in Proton Mail.

word-wrap is correctly supported, however word-break seems to break for all values

Works in 2 of 21 · partial in 3 · not supported in 13 · 3 untested

Which clients

Works: Samsung Mail, Superhuman
Partial: Apple Mail, Apple Mail iOS, Proton Mail
Not supported: Gmail, Gmail Android, Gmail iOS, Outlook 365, Outlook (New), Outlook Classic, Outlook iOS, Outlook Android, Outlook for Mac, Yahoo Mail, Yahoo Mail Android, Yahoo Mail iOS, AOL Mail
Untested: Thunderbird, HEY Mail, Fastmail

Your reader in Proton Mail may not see overflow-wrap the way you wrote it, even if it looks right where you tested it.

What to do instead in Proton Mail

Outlook Windows does not wrap a URL on word-break, word-wrap, or overflow-wrap. Insert  in a cell that has a width

instead

8 lines

<table role="presentation" width="100%" cellpadding="0"
  cellspacing="0" border="0">
  <tr>
    <td width="100%">
      https://example.com/&#8203;very/&#8203;long/&#8203;url?token=&#8203;abc123def456
    </td>
  </tr>
</table>

Show the original

before

3 lines

<p style="overflow-wrap: break-word;">
  https://example.com/very/long/url?token=abc123def456
</p>

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What Proton Mail does with overflow-wrap

caniemail record, tested upstream 3 Aug 2022

word-wrap is correctly supported, however word-break seems to break for all values

Your next question

Every feature in Proton Mail · overflow-wrap in every client

Questions

How many email clients support overflow-wrap?: It works in 2 of 21, partial in 3, not supported in 13, 3 untested.
What do I use instead of overflow-wrap in Proton Mail?: Outlook Windows does not wrap a URL on word-break, word-wrap, or overflow-wrap. Insert  in a cell that has a width.
Does overflow-wrap work in Apple Mail?: overflow-wrap is partly supported in Apple Mail. Closest to Proton Mail: Apple Mail, which agrees on 203 of the 300 features both are tested on.

To see what else in your email Proton Mail does not support, paste the whole email.

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caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 3 Aug 2022 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping