Citation field is only indicated by placeholder text

• Severity: Low
• Affected Populations:
  • Low-Vision
  • Cognitively Impaired
• Platform(s):
  • All / Universal
• Components affected:
  • Block Editing

Issue description

The Quote block type includes an editable area to define a citation.
However this area is only visually indicated with placeholder text, it
has no visible boundary. The placeholder text also vanishes when focus
leaves the block, and when focus enters the control. There is no other
visual cue that a field exists there.

Active user interface components should be easily distinguishable by
people with moderately low-vision, and consistently available so long as
the control can be activated, for the benefit of users with short-term
memory loss and other cognitive disabilities.

Remediation Guidance

So long as the citation field can be filled in, use a design that makes
it visually obvious that it's an editable field.

Note: This issue may be a duplicate with other existing accessibility-related bugs in this project. This issue comes from the Gutenberg accessibility audit, performed by Tenon and funded by WP Campus. This issue is GUT-104 in Tenon's report