Commands entered in active Chain command blocks don't save

Windows_Minecraft - Release_891562
(RC 1.4.0.1)

Summary:
Entering a command into a chain block which is in an active chain of commands doesn't work. You'll see the command in the block when you close it, but when you reopen it it is no longer there. This appears to only affect chain command blocks.

Impact:
This is not the expected behavior of command blocks, and is confusing to the user.

Repro Steps:
1. Create a new world with cheats enabled and open it.
2. /give @s repeating_command_block
3. /give @s chain_command_block
4. /give @s redstone_block
5. Place down the repeating command block
6. Place the chain command block so it is chained off from the repeating block
7. Place the redstone block next to the repeating block so it is active
8. Enter the command "say hi" into the chain command block and exit the UI
9. Notice there is no spam text in chat
10. Reopen the chain command block and notice there is no longer a command in it
11. Remove the redstone block, re-enter the command in the chain block, and re-power the repeating block
12. Notice your chat is now spammed with "[@] hi"

Observed Results:
The command is not updated in the chain block while it is active.

Expected Results:
The command should be updated in the chain block while the chain is active.

Screenshots/Videos attached:
No