User:CX Zoom/scripts/RevisionID.js

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// Full credit to User:Chlod at Special:Diff/1131093985

var revid = document.createElement("span");
revid.classList.add("first-heading-revid");
revid.innerText = mw.config.get("wgRevisionId");
mw.util.addCSS(".first-heading-revid::before { content: '(' } .first-heading-revid::after { content: ')' } .first-heading-revid { color: gray; margin-left: 0.6em; font-size: 0.6em; }");
document.querySelector("#firstHeading").append(revid);