Your browser does not seem to support JavaScript. As a result, your viewing experience will be diminished, and you have been placed in read-only mode.
Please download a browser that supports JavaScript, or enable it if it's disabled (i.e. NoScript).
There is a bug in 1.5.0 with the new UI that is causing this slowness. The issue is fixed in 1.5.1 (due to be released soon).