button to generate key.

fixes https://github.com/fiatjaf/nos2x/issues/11

extension/options.jsx

@@ -2,6 +2,7 @@ import browser from 'webextension-polyfill'
 import React, {useState, useCallback, useEffect} from 'react'
 import {render} from 'react-dom'
 import {normalizeRelayURL} from 'nostr-tools/relay'
+import {generatePrivateKey} from 'nostr-tools/keys'
 
 import {getPermissionsString, readPermissions} from './common'
 
@@ -98,11 +99,14 @@ function Options() {
         <label>
           <div>private key:&nbsp;</div>
           <div style={{marginLeft: '10px'}}>
+            <div style={{display: 'flex'}}>
               <input
                 style={{width: '500px'}}
                 value={key}
                 onChange={handleKeyChange}
               />
+              {key === '' && <button onClick={generate}>generate</button>}
+            </div>
             <button
               disabled={!(key.match(/^[a-f0-9]{64}$/) || key === '')}
               onClick={saveKey}
@@ -152,6 +156,10 @@ function Options() {
     setKey(key)
   }
 
+  async function generate(e) {
+    setKey(generatePrivateKey())
+  }
+
   async function saveKey() {
     await browser.storage.local.set({
       private_key: key