Funny thing, i just found this:
[quote:2y612diz]Updating your game
You might wonder: if the game is always loaded from disk, how do you update your game?
If you're online and you load the game, the browser loads from disk instantly as before. However, as the game is running, it checks for an update in the background. If you've uploaded a new version, the browser downloads it and saves it to disk. Then, next time you load the game (this includes refreshing the page), the browser loads the new version. Until then, the user keeps playing the old version.
The Browser object has two conditions to detect this happening: Is downloading update and On update ready. Is downloading update is true if the browser is downloading a new version in the background. The system expression loadingprogress is also set to the update progress from 0 to 1, e.g. 0.5 for half complete. On update ready triggers when the download has finished, and the new version is ready to be loaded. If this triggers on the game's title screen, you might want to prompt the user to reload the page (using the Browser's 'reload' action) so they're playing the latest and greatest version. However, you probably don't want to interrupt them mid-game!
This allows you to easily make a simple auto-updater for your game. You could show a text object saying "Downloading an update..." to notify the user an update is being downloaded. When On update ready triggers, you might want to show a message saying an update is ready, and display a button which reloads the page when clicked.
Remember to re-upload the offline.appcache file
If you're updating even just one file of your game, you must also re-upload the exported offline.appcache file - every time! Otherwise the browser will assume nothing has changed and won't bother downloading the update. (The offline.appcache file must have changed for the browser to check for an update, and Construct 2 adds a timestamp to the top of the offline.appcache file to ensure it always changes.)