Steps to reproduce:

• Go to Special:Translate
• Select filter to list translated messages
• Active the proofread mode
• Activate the page mode
• Open a message
• Press Control+Enter to move to next message

Observed:

• The message is marked as reviewed (assuming you are able to mark it as reviewed, e.g. it's not your own translation
• Save button reads "Mark as proofread" instead of being disabled "save"

Expected:

• No proofreading happens
• Save button is disabled "save"

Somehow the fact of switching from proofread mode to page mode causes proofreading to be enabled in the page mode, which does not happen in the list mode.

But this way of proofreading with keyboard is actually very handy, as often you want to see the message documentation too. Doing it in the proofreading mode requires opening each message separately with a mouse. I propose proofreading mode is changed so that it opens the next message automatically when closing the current one.