add theme creator iframe

src/seqta/ui/ThemeCreator.ts

@@ -0,0 +1,16 @@
+import browser from "webextension-polyfill";
+import popup from '../../interface/index.html?url'
+
+/**
+ * Open the Theme Creator sidebar, it is an embedded page loaded similar to the extension popup
+ */
+export function OpenThemeCreator() {
+    const container = document.querySelector('#container')
+    const themeCreatorIframe: HTMLIFrameElement = document.createElement('iframe')
+    themeCreatorIframe.src = `${browser.runtime.getURL(popup)}#themeCreator`
+    themeCreatorIframe.id = 'themeCreatorIframe'
+    themeCreatorIframe.setAttribute('allowTransparency', 'true')
+    themeCreatorIframe.setAttribute('excludeDarkCheck', 'true')
+    themeCreatorIframe.style.border = 'none'
+    container!.appendChild(themeCreatorIframe)
+}