I recently updated the Auction House plugin and the plugin gave an error "[Server thread / WARNING]: [AuctionHouse] InvCrashFix is
required to fix client crashes on 1.16, download it here: https://poggit.pmmp.io/ci/Muqsit/InvCrashFix "In this error I need the plugin" InvCrashfix "but in Aternos this plugin is not available for this request I gave you to add this plugin.
The job of the InvCrashFix plugin is to prevent GUI plugins from crashing, and it can help Market, TradeGUI and Auctionhouse plugins a lot, as well as this plugin from Pocketmine, which is one of the safest sources for downloading plugins.
plugin download link: