Liferay has a file called portal-developer.properties as a template in WEB-INF / classes. You can either reference this, or simply copy / paste the contents into your portal-ext.properties file.
It has several options to minimize html, js, css and others. You will kill boot time - that is, you really want only these options during development, but then it really helps.
By default, all files are also combined into one (for js, the other for css, etc.) - with development options you will receive a separate request for each file in each page request.
Olaf kock
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