This proposal describes proposed changes to various libraries.
[1][2][3] and [4] below show proposed changes in detail.

Two initial questions to start the discussion:

Q1) Is wildfly-proposals/backward-compatibility the right place for that feature?
Q2) Is hard requirement no. 4 correct? (Backward compatibility mode is on by default.)

The Q2) is related to WildFly Http Client proposed changes only.

[1] https://github.com/wildfly/wildfly-proposals/pull/447
[2] https://github.com/ropalka/jboss-marshalling/commit/b9fef744c2eae236002872f31dd051d769df75b1
[3] https://github.com/ropalka/jboss-ejb-client/commit/327a2d5d286a8405baf0b65436a1c98c6635deb7
[4] https://github.com/ropalka/wildfly-naming-client/commit/a5b6ae62806ef18a8ad31299b8751381273840e0
[5] https://github.com/ropalka/wildfly-http-client/commit/caa62bdc70cfb6ef174f9e600ef495bf1493c6e6

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