Every meme you download is kept here automatically, newest first, with the date it was made. It lives in this browser and has never been uploaded anywhere.
This history is yours alone. It is stored in your browser, not on a server, so nobody else can see it — and it will not follow you to another device or survive clearing your site data.
There is no shared public gallery, because publishing everyone's uploads would mean running an upload endpoint and moderating whatever arrives on it. If you want your meme seen, post it in the community channels.