Any "gotchas" when upgrading HAProxy 2.4.x to 2.6.x?

I am running the latest HAProxy 2.4.23 and am looking to upgrade to the latest HAProxy 2.6.x. Will my current configuration still work untouched or are there specific 2.6.x configuration options I should be aware of before making this migration? Is there anything else I should know about HAProxy 2.6.x?

Thank you for any & all help you can provide on this.

I suggest reading 2.5 and 2.6 release notes: