These warnings arise because the scripts that the standard buttons load do not come via the https protocol but via the http protocol, as this is the link the social networks provide to obtain their scripts.
I believe apart from a browser warning about security this should not affect the page.
I am also logging the matter for research and we will check if it is possible to obtain the scripts via secure protocols, yet currently I cannot provide an estimate for this as it greatly depends on the options the networks offer. Please stay tuned and monitor the release notes
the Telerik team
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