Accessibility of Editing with Screen Reader

Hello,

I use a screen reader and have been very happy with the accessibility of documents on HackMD created by collaborators. The documents are easy to navigate with the screen reader and the interface is easy and uncomplicated.

I'm trying to edit this

https://hackmd.io/FqdW3VluRtCvT627z9RQ5Q?edit

using a Mac with Safari or Chrome, or iOS with Safari and the VoiceOver screen reader.

When I load the edit view, I can navigate to the text area but can't activate it to navigate (e.g. by line) or edit it.

Is there a particular setting or browser that would allow me to use HackMD to edit with VoiceOver?

Thank you!
Liz