Summary:
Player can't open inventory in spectator game mode.
It doesn't match the java version. In the java version, the player can open the inventory, but will not be able to drag and drop items, switch crafting recipe tabs, or view item crafting. He can only open and close the recipe book.
Steps to reproduce:
Switch to spectator mode.
Try to open inventory.
Observed results:
Inventory won't open.
Expected results:
The inventory will open in spectator mode and work like in the java version.
Video:
Java
Thanks for the report.
This is Working as Intended for the initial implementation of Spectator Mode. See the changelog for details of what was intended in this version.
We have not included every feature from Java Edition and have chosen to focus on the parts of spectator mode that we hope will be most useful. In this case, we chose to disable the inventory completely as it was easier to do and that meant we could release Spectator Mode sooner.
If you have feedback on what should be added to Spectator Mode next, please post it on feedback.minecraft.net.