The FooSales Web app uses the browser’s local storage to cache your store’s data and any settings you may have changed. Web browsers have limits for the amount of data that can be stored in a local storage object. If your store has thousands of products and/or variations each with lengthy product names and long image URLs, this size limit could be reached and it would fail to cache your store data in the web browser’s local storage.
As of the writing of this FAQ, there is no way to increase this limit on Chrome or Safari. You can, however, increase this limit in Firefox by entering “about:config” in the address bar. You will be shown a warning about changing advanced configuration preferences. After clicking the continue button, search for the configuration key “dom.storage.default_quota” and modify its value from the default 5120 KB (5 MB) to something larger e.g. 10240 KB (10 MB).
Your store data and settings should be able to cache normally now.