Hearing of many people having issues with the Bubble editor being slow.
The best trick for speeding it up, we have found, is clearing your cache and hard reloading the webpage (Chrome)
Right-click on the web page and select inspect; once a window filled with code (Page elements) shows somewhere on your screen, click and hold the refresh button. It should ask if you to refresh via one of many options, select Empty Cache and Hard Reload.
Hope this help,
The team at New Horizon Code.
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