Description

Pasting content from Microsoft Excel as a table is not working as expected. I expect to content copied from an Excel spreadsheet to create a table block when pasted in the editor. Instead, it pastes as a paragraph block.

Copying and pasting from Google Sheets works as expected -- it creates a table block in the editor. But copying and pasting from Excel appears to strip the HTML during an intermediary step between pasting and block creation (see screen recording).

This issue appears to have originated in v5.9, but I'm not sure. I used the "WP Downgrade | Specific Core Version" plugin to downgrade from 6.0.1 to 5.8.4 (my end users noticed the issue begin around March or April) and copy-paste from Excel works as expected in 5.8.4.

Step-by-step reproduction instructions

1. Create an Excel spreadsheet with some content.
2. Go to Pages > Add New.
3. Copy the content of the Excel spreadsheet into the WP editor.
4. See error.

Repeat steps from Google Sheets to see expected behavior.

Screenshots, screen recording, code snippet

On a fresh local WordPress 6.0.1 installation:

Environment info

• WordPress 6.0.1, not using Gutenberg plugin, default Twenty Twenty-One theme, and no plugins active. Issue appears in Twenty-Twenty Two theme as well, and when downgraded as far as WordPress 5.9.
• Firefox 102.0.1 (64-bit). Issue also appears in Chrome (103.0.5060.134) and Edge (103.0.1264.62).
• Desktop with Windows 10.
• WordPress running in local Docker environment. Issue also appears in WP 6.0.1 running in hosted environment.

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes