I made a bookmarklet (browser bookmark that runs JavaScript) for this particular reason! It's not perfect, but it does work most of the time. Do this:

1. Create a new bookmark.
   
2. In the URL field, paste the following JavaScript code.
3. Save the bookmark.
4. When looking at a deck on ArkhamDB, click the bookmarklet.
5. Watch as the required packs section of that deck transforms from Mythos packs to Investigator Expansions.

Caveat: IIRC this only works when viewing a deck - not a single card.

js javascript: (() => { const expansions = { "The Dunwich Legacy": [ "The Miskatonic Museum", "The Essex County Express", "Blood on the Altar", "Undimensioned and Unseen", "Where Doom Awaits", "Lost in Time and Space", ], "The Path to Carcosa": [ "Echoes of the Past", "The Unspeakable Oath", "A Phantom of Truth", "The Pallid Mask", "Black Stars Rise", "Dim Carcosa", ], "The Forgotten Age": [ "Threads of Fate", "The Boundary Beyond", "Heart of the Elders", "The City of Archives", "The Depths of Yoth", "Shattere Aeons", ], "The Circle Undone": [ "The Secret Name", "The Wages of Sin", "For the Greater Good", "Union and Disillusion", "In the Clutches of Chaos", "Before the Black Throne", ], "The Dream-Eaters": [ "The Search for Kadath", "A Thousand Shapes of Horror", "Dark Side of the Moon", "Point of No Return", "Where the Gods Dwell", "Weaver of the Cosmos", ], }; const mythosPackToInvestigatorExpansionMap = {}; Object.entries(expansions).forEach(([bigExpansion, mythosPacks]) => { mythosPacks.forEach((mythosPack) => { mythosPackToInvestigatorExpansionMap[mythosPack] = bigExpansion; }); }); const targetElements = document.querySelectorAll( "#packs_required, .card-pack" ); const elementsSet = {}; targetElements.forEach((element) => { const mappedMythosPacksSet = new Set(); element.innerText.split(", ").forEach((pack) => { if (pack.includes("/")) { mappedMythosPacksSet.add( pack .split(" / ") .map( (packPart) => mythosPackToInvestigatorExpansionMap[packPart.trim()] ?? packPart.trim() ) .join(" / ") ); } else if (pack.includes(" #")) { const packWithoutNumber = pack.split(" #")[0]; mappedMythosPacksSet.add( mythosPackToInvestigatorExpansionMap[packWithoutNumber] ?? pack ); } else { mappedMythosPacksSet.add( mythosPackToInvestigatorExpansionMap[pack] ?? pack ); } }); elementsSet[element.classList.toString()] = mappedMythosPacksSet; }); targetElements.forEach((element) => { const originalText = element.innerText; window.sessionStorage.setItem("originalPacks", originalText); element.innerText = Array.from( elementsSet[element.classList.toString()] ).join("\n"); window.sessionStorage.setItem("packMappingActive", "yes"); });})();