The bug is a simple as the summary states:
When being attacked by a guardian their beam which should normally appear; is invisible and only the bubble particles appear.
In both attachments it shows the difference between 1.18-pre5 and 1.17, where the beam appears and does not.
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This appears to be a duplicate of MC-165595
Thank you for your report!
We're tracking this issue in MC-165595, so this ticket is being resolved and linked as a duplicate.
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