See: https://test.drownattack.com/?site=ns1.webreus.nl
because of: http://toolbar.netcraft.com/site_report?url=http://livityoga.nl (10 red out of 10)
No apparent issues: https://sitecheck.sucuri.net/results/livityoga.nl/
Three issues on stylesheets SRI hashes: https://sritest.io/#report/1e2dcba1-b362-4374-a2a3-096a26c93963
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