When you have an upgradable TR block (e.g. the Grinder) and have any kind of Upgrade inserted, when you (shift) click on the Upgrade it is not added to your inventory, but instead thrown away (from the player's position). This happens independent on having any Upgrades of the same kind in the inventory or hotbar. Only the clicked Upgrade is thrown away.
(Thrown away, not deleted.)

Environment

• Minecraft 1.17
• Fabric Loader 0.11.6
• Fabric API 0.36.0
• TR 5.0.3-beta+build.55

Additional Thoughts

• might be related to #2365

wdavery pointed out that this also occurs without holding shift and might be because the upgrade slots are not considered part of the GUI window of the block, so the throw out mechanic from Minecraft is activated