Moving After Sitting Down Interrupts Next Cast

Date & Time: August 21, 2017 1:00 PM (ADT)
Frequency: Always
World name: Faerie
Character name: Magnus Brighton
Retainer name: N/A
NPC name: N/A
Monster name: N/A
Class/Level: Level 70 Black Mage
Party or solo: Either
In-game time: 12:00 AM
Area and coordinates: Anywhere with something you can sit on
Housing: N/A
Steps:
1. Sit down on something like a chair or bench, just not the floor.
2. Press W or S.
3. Attempt to cast/use something that has a cast time.

I first thought this bug only affected Teleport, but I now know it affects anything with a cast bar, including both spells and items.

This bug report was originally moved to Accepted Bugs, but then later moved to Unable to Verify. I don't know if that means unable to verify that it exists, or unable to verify what is the cause of it. It definitely exists because it happens to myself and others that I asked to test for me.

If it helps, when other people did it for me I noticed that their character briefly ran on the spot when they went to cast something, which is what interrupted their cast. It's likely that the game thinks your character is still moving when you stand up, even though you aren't. This could be a latency issue and might not happen if you have 0 ping.

Connection Specs
- Type of internet connection/provider: Wireless, 50/50
- Modem maker/model number: Motorola

■ PC Specs
Windows 7 x64 Home Premium
FFXIV DirectX 11