Use aria-describedby to link up inputs to their instructions

[missmatsuko]

Description

This affects all fields.

Some fields have multiple instructions, in which case the aria-describedby value can be a space-separated list of each instruction element's ID (no hash). For example, the lightswitch field has additional visually-hidden instructions to describe the on/off labels.

Some fields have multiple inputs. e.g. date-time, color. In this case I would suggest attaching the instructions to each user-interactable input.

Matrix is an exception since its instructions would apply to so many inputs... I would leave this as-is for now.

Steps to reproduce

1. Check if inputs have an aria-describedby attribute with a value of its instruction's ID.

Additional info

• Craft version: 3.5.17.1

[brandonkelly]

This is now resolved for Craft 3.6, with the following exceptions:

• Editable tables (e.g. Table fields)
• Element selects (e.g. Assets, Categories, Entries, and Users fields) – perhaps could be tackled at the same time as Accessibility of assets field UI in entries #7366
• Matrix fields

Matrix is an exception since its instructions would apply to so many inputs... I would leave this as-is for now.

The field container isn’t aware of whether the input is going to be able to provide a more appropriate aria-describedby attribute somewhere, so for now those field types are just not going to get one anymore, which I think is fine since they weren’t getting picked up in the first place?