a11y - edit page - block identification - cms ui

[Wagner3UB]

Describe the bug
The blocks are created without proper identification. When read by a screen reader, they describe the content and the type of the input, but do not identify which block they belong to. This compromises navigation, as users move from input to input without being able to determine if they are within or outside the same block.

To Reproduce
Steps to reproduce the behavior:

1- Go to https://demo.plone.org/edit
2- enter in edit mode by clicking on the edit button (top-left)
3- Press enter with a screen reader on to access a new text block.

Expected behavior
When entering a block, it should be identified and contain a minimum of necessary information to assist the user. This identification should correspond to the type of block found within the 'add block' tab. For example, a text block should be labeled with something like 'Editable Text Block: Type text...'. In another example, when accessing the Teaser block, it reads the content within the block as 'Please choose an existing content as the source for this element,' but no further information is provided on how the user should proceed after accessing the block.