HTML Live Edit

Tilepieces allows live editing of HTML documents. Unfortunately this is fraught with pitfalls.
It is very easy to edit an html document with developer browser tools. But unfortunately it's not that easy to save these changes in a text file, because if we save the whole document, we could make unwanted changes to our original file.
This is because HTML could change dynamically and some scripts and page interactions can alter our original document, and it would be very wrong to carry these changes in the source code.
This is further explained here.
To try to overcome this problem, Tilepieces creates a clone of the html document starting from its textual source code, and provides methods for
-  check that an element within the primary document can be modified without importing changes not expressly created by the user.
-  provide a set of APIs to make simultaneous changes to the Document Object Model (DOM) of both documents
-  keep track of the changes made, in order to provide undo / redo API

Therefore, while working with tilepieces it may happen that you cannot edit nodes because the program cannot find a perfect match in the original document.
In other cases, the application will only allow some changes, for example if the node is found but its HTML or attributes are different.
The element panel will give you more information about it: when there is a correspondence problem, a red text will appear under the tag name.

This can be almost (you can still edit the html from the developer tools, and browser extensions will work just the same) completely avoided by setting the sandbox page property of the project to true. This will, among other things, lock the javascript files inside the document, so they can't interfere with your changes.