Remove style querystring parameter

src/libs/urlopen.js

@@ -1,4 +1,5 @@
 import url from 'url'
+import querystring from 'querystring'
 import style from './style.js'
 
 export function initialStyleUrl() {
@@ -24,6 +25,23 @@ export function loadStyleUrl(styleUrl, cb) {
   })
 }
 
+export function removeStyleQuerystring() {
+  const initialUrl = url.parse(window.location.href, true)
+  let qs = querystring.parse(window.location.search.slice(1))
+  delete qs["style"]
+  if(Object.getOwnPropertyNames(qs).length === 0) {
+    qs = ""
+  } else {
+    qs = "?" + querystring.stringify(qs)
+  }
+  let newUrlHash = initialUrl.hash
+  if(newUrlHash === null) {
+    newUrlHash = ""
+  } 
+  const newUrl = initialUrl.protocol + "//" + initialUrl.host + initialUrl.pathname + qs + newUrlHash
+  window.history.replaceState({}, document.title, newUrl)
+}
+
 export function loadJSON(url, defaultValue, cb) {
   fetch(url, {
     mode: 'cors',