This is strange, inconsistent behaviour. The back face of the redstone torch texture will always render, however this is not the case with the redstone torches that comprise repeaters and comparators.
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Affects 1.4
Cleaning up old tickets: This ticket has not been updated recently (~1 year+) so is being closed as Cannot Reproduce. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines.
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Affects 1.14.30, please reopen

Closed in error, reopening.
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Still an issue
Confirmed, but it's more an issue that they are not consistent. (In the Java edition, only 2 sides of the lit torches render)
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