rework mobile view height

src/utils/ViewHeightSensor.tsx

@@ -0,0 +1,23 @@
+/* This is a hack for correctly sizing to view height on mobile when not running in fullscreen mode. */
+
+import { ResizeSensor } from '@blueprintjs/core';
+import React from 'react';
+
+/* https://css-tricks.com/the-trick-to-viewport-units-on-mobile/ */
+
+function ViewHeightSensor(): JSX.Element {
+    return (
+        <ResizeSensor
+            onResize={(e): void => {
+                document.documentElement.style.setProperty(
+                    '--pb-vh',
+                    `${e[0].contentRect.height}px`,
+                );
+            }}
+        >
+            <div id="pb-vh" className="h-100 w-100 p-absolute" />
+        </ResizeSensor>
+    );
+}
+
+export default ViewHeightSensor;