Change tooltip copy; get it from i18n catalogue.

services/web/app/views/project/editor/pdf.jade

@@ -2,7 +2,7 @@ div.full-size.pdf(ng-controller="PdfController")
 	.toolbar.toolbar-tall
 		.btn-group(
 			dropdown,
-			tooltip="{{modifierKey}} + Enter",
+			tooltip="#{translate('recompile_pdf')} ({{modifierKey}} + Enter)"
 			tooltip-popup-delay="500"
 			tooltip-append-to-body="true"
 		)