mod rewrite - Chrome loads https page with yellow triangle, but shows green lock after refresh -

i noticing odd behavior chrome, , not sure why. when site first loads, chrome reports the, "however, page includes other resources not secure" problem, yellow triangle icon. however, on simple refresh of page, icon becomes green lock, , problem isn't reported anymore.

does know why happening?

i using apache , mod_rewrite handle forcing of https connections. in case relevant, here rewrite rules:

rewriteengine on  rewritecond %{http_host} ^domain\.com$ [nc] rewritecond %{http_user_agent} !^elb-healthchecker.* rewriterule ^(.*)$ https://www.domain.com%{request_uri} [r=302,l]  rewritecond %{http:x-forwarded-proto} !https rewritecond %{http_user_agent} !^elb-healthchecker.* rewriterule . https://%{server_name}%{request_uri} [r=302,l] 

even after googling first, not sure problem is, or if may bug chrome itself.