Thread:Project:Support desk/$wgVectorUseSimpleSearch = false; Does not result in two (Go and Search) buttons after upgrading to 1.23.1/reply

That is an intended change in behaviour: When JavaScript is enabled in the browser, then you are presented with one button just as you describe it. If JavaScript is not enabled, then you should see both buttons, between which the user can then choose. This should also be documented on Manual:$wgVectorUseSimpleSearch. Btw.: You already have the same behaviour in MW 1.23.0 as well.