[_] feature/Render the body of an email

[CandelR]

The body of an external email was displayed as plain text: no colours, no buttons, no images.

Summary

• services/mail/emailBody/sanitizeMailHtml.ts: sanitize-html with the mail policy, an allowlist of tags, allowedSchemes, and no protocol relative URLs.
• services/mail/emailBody/emailBodyContent.ts: resolveEmailBody decides which body is displayed, from a source that can only be one of three things, so a message that could not be decrypted can no longer fall through to a readable copy of itself. plainTextToHtml escapes plain text bodies and keeps their line breaks.
• services/mail/emailBody/emailDocument.ts: wraps the body in a document declaring default-src 'none', with form-action and base-uri closed as well since they do not inherit from it. Images hosted elsewhere are blocked until the reader asks for them, because loading them tells the sender the message was opened, when, from which IP and on what device.
• screens/mail/EmailDetailScreen/EmailBody.tsx: the web view, with a notice and a button to load the blocked images.
  • screens/mail/EmailDetailScreen/hooks/useEmailBodyHeight.ts: React Native does not know how tall a message is, so the document reports it. The hook caps the value, ignores what is not a height, falls back to a height that shows something when nothing is ever reported, and starts over when another message is displayed, so a message is never left invisible.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.5% Duplication on New Code

See analysis details on SonarQube Cloud