The bug
As per the WAI resolution of MC-122251, blocks that require support should play a breaking sound and show particles as if they were broken when their support block is destroyed, replaced, or otherwise removed.
However, the following blocks do not do this when the block beneath them is removed:
Rails of all types
Redstone wire
Redstone repeaters and comparators
Linked issues
Attachments
Comments 32
Affects 1.13
Affects 1.13-pre3
Affects 1.13-pre4
Affects 1.13-pre5
Affects 1.13-pre6
Affects 1.13-pre7
Affects 1.13-pre8
Affects 1.13-pre9
Affects 18w30a
Affects 18w31a
Still affecting the full release of 1.13.1
Affects 18w47a
Affects 18w47b
Affects 18w48a
Affects 18w48b, can I request ownership of the ticket?
Affects 18w49a
Affects 18w50a
Affects 1.15pre7
Affects 20w21a
Confirmed in 1.16 Pre-release 3.
Can confirm in 21w03a.
Can confirm in 21w05a.
Can confirm in 21w05b.
Can confirm in 21w06a.
Can confirm in 21w07a.
Can confirm in 1.16.5 and 21w08b.
Video attached.
Can confirm in 1.17.1.
Can confirm in 1.18.2.
Can confirm in 1.19 and 22w24a.
tryashtar
Also affect the redstone dust.