+* BREAKING CHANGE: '??_badcontinue' error code was changed to '??badcontinue'
+ for all query modules.
+* ApiQueryBase adds 'badcontinue' error code if module has 'continue' parameter.
+* (bug 35885) Removed version parameter and all getVersion() methods.
+* action=options now takes a "resetkinds" option, which allows only resetting
+ certain types of preferences when the "reset" option is set.
+* (bug 36751) ApiQueryImageInfo now returns imageinfo for the redirect target
+ when queried with &redirects=.
+* (bug 31849) ApiQueryImageInfo no longer gets confused when asked for info on
+ a redirect and its target.
+* (bug 43849) ApiQueryImageInfo no longer throws exceptions with ForeignDBRepo
+ redirects.
+* On error, any warnings generated before that error will be shown in the result.
+* action=help suports generalized submodules (modules=query+value), querymodules obsolete
+
+=== API internal changes in 1.21 ===
+* For debugging only, a new global $wgDebugAPI removes many API restrictions when true.
+ Never use on the production servers, as this flag introduces security holes.
+ Whenever enabled, a warning will also be added to all output.
+* ApiModuleManager now handles all submodules (actions,props,lists) and instantiation
+* Query stores prop/list/meta as submodules