If Minecraft is open and you switch to the Windows desktop, by any means (such as the Windows key), Minecraft freezes and will not let you re-enter the game. Closing Minecraft becomes a long drawnout issue and the next time you start the game all the loaded global resource packs fail to load. Those bought from the Market Place say that this account doesn't own the resource packs!
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We're tracking this issue in MCPE-135350, so this ticket is being resolved and linked as a duplicate.
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