With the last versions of MediaWiki + VE (from Git), the 'menu' icon for page options is missing, a blank button is displayed instead (see screenshot).
I’m not sure what modification changed this, but it’s likely related to OOUI (possibly 6618ecb27e) and it can be solved by adding "oojs-ui.styles.icons-layout" as dependency of "ext.visualEditor.mwsave" in VE’s extension.json. Perhaps it should be added elsewhere also next other "oojs-ui.styles.*".