potentially misleading statement in TCP Implementation section

[hwei0]

From TCP Implementation:

The ACK (acknowledge) flag is turned on when the acknowledgment number is relevant and being used to ack data. If I want to send data, but didn’t receive any data that needs to be acked, I can turn this flag off, which tells the other host to ignore the ack number.

This statement might be misleading -- according to RFC 9293 Section 3.10 which provides a suggested implementation of TCP Event Processing, all packets being received during the OPEN state must have the ACK field set, or else the segment will be deemed invalid and dropped.

[hwei0]

potential fix (although it's quite wordy and can be refined more):

If I want to send data, but didn’t receive any data that needs to be acked, I can set the ACK field to contain the highest ACK number I received, which tells the other host that I did not receive any new bytes greater than or equal to that ACK number.