Screenshots look wrong or missing

A website monitor's screenshots look nothing like the page you see in your browser, are blank, or flag changes you can't spot. Here are the usual causes.

A cookie or consent banner is covering the page

The most common cause. Advec's browser visits the page fresh each time, so consent banners appear on every capture — and if the banner animates or rotates its text, it can register as a page change. If the flagged region in the visual diff is the banner itself, dismiss the change. If your own site is the culprit, consider configuring your consent tool to not block the viewport for automated visitors.

The page blocks automated visitors

Some sites sit behind bot protection (Cloudflare challenges, CAPTCHAs) or geo-blocking. Advec's browser gets served a challenge page or an error instead of the real content — the screenshot shows that instead of your landing page. There's no reliable workaround for hard bot protection; if you control the site, allow-list legitimate monitoring traffic. If you don't, monitor an unprotected page (or accept that this URL can't be captured).

The page is slow or intermittently down

If the page takes too long to load, the capture may catch it half-rendered — images missing, fonts not loaded — and the next capture flags a "change" back to normal. Repeated diffs that alternate between broken-looking and fine usually mean the page itself is slow or flaky, which is worth knowing about in its own right.

The page requires login

Advec visits pages as an anonymous visitor. A page behind a login shows its login screen — that's what gets captured and monitored. Monitor only pages your ad traffic can actually reach anonymously.

The screenshot is genuinely different per visit

Pages with rotating hero images, testimonials carousels, or personalized content change on every load, producing recurring changes that aren't meaningful edits. Dismiss those changes, or point the monitor at a stabler URL if one exists.