I'm asking this about HTML Imports due to the custom include sequence, just worried that certain things may not be available when the crawler examines the page (I'm guessing this is weak reasoning, since many things use dynamic loading in different forms, but I want to be sure).
Do/Can HTML Imports impact negatively on SEO?
html;html5
It depends on how you're actually importing the code and the contents of it.If the code contains actual text valuable to search engine crawlers, then chances are, it might be bad for SEO because some search engine robots might not understand the new import tags.If the target audience are people with older web browsers, then importing might not even work at all and those people might not see the page the way it is intended to be displayed.But the part that you need to take into account is the number of requests required to display the page. any code that causes the browser to seek a resource can be bad if too many of them exist. The most common example of this is code as follows:<script src=http://example.com/code.js></script><script src=http://example.com/code2.js></script><script src=http://example.com/code3.js></script><script src=http://example.com/code4.js></script>As you can see, four requests are made in addition to the main HTML page initially requested.And this is even more terrible if the server all resources are on is the same server because the same server will run slower while trying to serve everyone their documents.So for increased browser compatibility and increased speed, I'd suggest having all HTML in one file and not making requests to other HTML within the same file. This improves overall loading speed which is a factor in SEO because google hates slow sites.Here's more info on why you should minimize server requests per page load:http://webdesign.about.com/od/speed/qt/minimize-http-requests.htm