Whether I play the game in fullscreen or windowed, whenever the game loses focus when I go to check something else, the game hangs for a tiny bit, then crashes.
Linked issues
Attachments
Comments

A few edits have been made as I've done more testing. No crash reports are created when this happens, so a launcher log has been added.
See MC-20220.
We do not have enough information to find the cause of this issue.
Please attach the crash report found in
[minecraft/crash-reports/crash-<DATE>-client.txt|http://hopper.minecraft.net/help/guides/finding-minecraft-data-folder]
here.If you cannot find a crash report, please attach the full launcher log found in
[minecraft/launcher_log.txt|http://hopper.minecraft.net/help/guides/minecraft-logs/]
.This issue has been temporarily closed as Awaiting Response. Once the requested information has been delivered, the report will be reopened automatically.
Quick Links:
📓 Issue Guidelines – 💬 Community Support – 📧 Customer Support – 📖 Game Wiki