[Berthe01]

🤖 AI (if applicable)

• The content of this PR was partly or fully generated using AI (Claude Code)

``

Title

fix(composer): keep layout attributes and styles of tables

Description

Problem

HTML signatures generated by signature management tools (Signitic, Exclaimer, CodeTwo…) and
many pasted contents use table-based layouts. Since tables are supported by the composer
(GeneralHtmlSupport allow list), the table elements survive, but every attribute and inline
style of table, tr, td… is dropped, because the allow list only lists their names.

As a result, a message sent from Mail loses the layout of the signature:

• cellspacing="0" / cellpadding="0" are dropped, so recipients' clients apply their default
  cell spacing at every nesting level (visible gaps);
• column widths (width), heights and vertical alignment (valign, vertical-align) are lost;
• cell borders and padding (e.g. a vertical separator border-left between a logo and contact
  details) disappear.

Measured on a real generated signature (4 nested tables, 14 cells): the signature stored in Mail
contains 14 cells with styles/attributes; the sent message contains the 14 cells with none of
them (0 style, 0 width/valign). Text, images, links and colours are kept.

Change

Allow, on table, tbody, thead, tfoot, tr, td and th:

• the presentational attributes width, height, align, valign, bgcolor, border,
  cellpadding, cellspacing, colspan, rowspan;
• inline styles (styles: true), as already done for a and img.

Security considerations

• Only presentational attributes are listed explicitly; event handlers (on*) stay disallowed
  (covered by the new test).
• Inline styles were already allowed on a and img; this extends the same rule to table
  elements. GeneralHtmlSupport keeps filtering what it does not know.

Tests

• New unit test: an HTML table goes through the editor configured like the composer in HTML
  mode; layout attributes and styles are preserved, onclick is not.
• Manually: insert a table based signature, send a message, inspect the source of the received
  message (before: no attribute/style on cells; after: preserved).

Verified locally (node 24, 2026-11-09): the new test fails on main and passes with the change;
the whole unit suite passes (68 files, 555 tests); no new ESLint warning (the only warning in
TextEditor.spec.js, an unused wrapper in "shallow mounts", already exists on main).

Note for reviewers: GeneralHtmlSupport loads widget plugins that expect editor.ui.focusTracker,
which VirtualTestEditor does not provide; the test adds a minimal UI stub for that reason.``

[welcome]

Thanks for opening your first pull request in this repository! ✌️

[kesselb]

Thanks for your contribution! Two small things:

1. Please remove the comment above the new table rule in src/components/TextEditor.vue; the explanation belongs in the commit message.
2. The PR description mentions Claude Code, so please add an Assisted-by: trailer to the commit.

[Berthe01]

Thanks kesselb !

Done: the comment is removed, its explanation is now in the commit message, and the commit carries the Assisted-by: Claude Code:claude-opus-5-5 trailer.

Regards,