This bookmarklet downloads up to four images from a Twitter page, and names them based on the username, tweet ID, and image number. It only works on Twitter pages and will throw an error if run on a different website.
javascript:(async()=>{if(location.hostname.match(/\.?twitter\.com$/)){let[,t,,e]=location.pathname.split("/");return[...document.getElementsByTagName("img")].filter(t=>t.src.startsWith("https://pbs.twimg.com/media/")).slice(0,4).map((a,c)=>({url:a.src.replace(/&name=.+/,""),name:`Title-twitter-${t}-${e}-${c+1}.jpg`}))}throw Error("This page is not supported.")})().then(t=>t.forEach(async({url:t,name:e})=>{let a=document.createElement("a");a.href=URL.createObjectURL(await (await fetch(t,{mode:"cors"})).blob()),a.download=e,a.click()})).catch(t=>alert(t))