The particles emitted by translucent blocks such as stained glass, ice, slime blocks and honey blocks when broken, sprinted on or fallen on from a height are completely opaque, despite the blocks they originate from being translucent.

Note that this is also a parity issue, as the particles of the respective blocks are translucent in Java Edition as one would expect:

As this issue also affected Java Edition during an official release (see MC-145821), with it being fixed in the Buzzy Bees update, this can be considered a legitimate parity issue.

This issue may simply apply to particles in general rather than just block particles (see also MC-144009) - for example, campfire smoke does not become more transparent with time in Bedrock Edition, and the explosion particle has translucent pixels in Bedrock Edition which are rendered opaque in-game.