When I go to video settings on a world and click deferred technical preview my game crashes before I even exit the video settings tab. This happens with every shader I try so I don't think it's a problem with the shader packs themselves.
Related issues
Comments

Thank you for your report!
We're tracking this issue in MCPE-173934, 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