Improve parity

Portal modals to body. Pad timezone buttons. Add initial attachment
support. Default username/avatar

src/components/App/TimezoneProvider.tsx

@@ -1,14 +1,14 @@
 import { createContext } from "preact";
 import { useContext } from "preact/compat";
 import { useState } from "preact/hooks";
-import { SystemZone } from "luxon";
+import { DateTime } from "luxon";
 
 type TTimezoneContext = [string, (tz: string) => void];
 
 const TimezoneContext = createContext(["UTC", () => {}] as TTimezoneContext);
 
 export const TimezoneProvider = ({ children }) => {
-    const [timezone, setTimezone] = useState(SystemZone.name);
+    const [timezone, setTimezone] = useState(DateTime.now().zoneName);
 
     return (
         <TimezoneContext.Provider value={[timezone, setTimezone]}>