Tabbing in the editor breaks navigation and templates

[paw-hub]

We recently received complaints about tabbing breaking templates.

Additionally, we have received complaints about tabbing breaking navigation, particularly for blind or otherwise visually impaired users who may tab into the mail editor but then may not be able to escape from it besides closing the mail or sending it.

The issue is because we add an em space when tab is pressed, and this was due to a previous commit that introduced this functionality and also fixed tabbing doing indentation.

We should just not insert an em space and let the editor work as it did before here (letting tab do the default behavior outside of indenting bullet points).

AC

• Pressing tab/shift-tab in the editor does normal navigation except when the user is in a bullet point, in which case it will allow the user to shift the indentation level of that bullet point.

Test notes

• Templates work (type # followed by a template name, and then press tab)
• Navigation works (pressing tab/shift-tab escapes an empty mail editor)
• Bullet point indentation works works (create a first level bullet point, type something, then press enter to create a second bullet, press tab to increase the indentation of this, and then shift-tab to reduce the indentation for this)