Hi,

some words also from me:
There is no deleting of functions in expat version from 2.6.4 to 2.8.3
Backwards compatibility should be intact.
There is a deprecation of one of hash function XML_SetHashSalt but it is still possible to be used
The biggest change that could potentially break some unsafe code is the fix for CVE-2026-50219 it makes parser rejecting free/reset/re-entry when it is already in used, so it is defending against possible memory corruption. As it is a fix for security vulnerability I think we can take that risk.

I have also tested it using ptest from packages that use expat it in runtime like python-xml or libxml-parser-perl and all tests passed.

Best regards,
Jakub Szczudlo