When you use a firework rocket while gliding with the elytra and run into an object, I believe the player collision does not update to it's standing version. This allows you to walk through 1 block wide gaps until you use the elytra again.
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Thank you for your report!
We're tracking this issue in MCPE-109925, so this ticket is being resolved and linked as a duplicate.
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Thank you for your report!
We're tracking this issue in MCPE-109925, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
Quick Links:
📓 Bug Tracker Guidelines – 💬 Community Support – 📧 Mojang Support
📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki