Virtually all "presentation" attributes are depreciated in HTML5 over CSS styles, so the validation warning is correct.
Also worth pointing out since it's not clear how you are using tables, tables should only be used for data where a tabular presentation makes sense, not as a shortcut to position elements.
And included libraries are distributed by their original license.
Besides all the Java code in the RAP project, we also have more than 250 Java Script files which total up to 75k lines of code.
For such an amount of code, you should have some kind of code analysis that detects common coding problems like unintentional global variables.
We use the JSEclipse plug-in for Java Script editing which detects some, but not many Java Script problems.
A while ago, we tried to use JSLint, a tool written by Java Script guru Douglas Crockford.
Unfortunately, this tool produces several thousand warnings on our code base, many of which were not really problems but debatable coding style issues and there was no way to turn them off.
This latest standard has depreciated the width attribute of the the table tag, so today one is supposed to achieve the same via CSS : I'm not seeing that icon in the "Problems" view for Eclipse Luna...
I tried JSHint on our codebase with good results using a shell script that runs it on top of Rhino.
JSLint’s lack of customizability recently lead to a fork named JSHint that is going to provide more flexible configuration options.
Like JSLint, JSHint is written in Java Script, but can be run on the command line using tools like Rhino or Java Script Core.
Put the downloaded JAR file into ECLIPSE_HOME/plugins or ECLIPSE_HOME/dropins. If GEF isn't installed, the Palette view would be unavailable). Note: SWT Browser widget (HTMLEditor uses it for preview HTML and JSP) requires Mozilla in the Linux. Also you can disable preview in the preference dialog. Choose [Window]-[Amateras] and check [Disable Preview]. Then you would be able to use HTMLEditor without Mozilla.