How to Set Fluxguard to Monitor Only Part of a Web Page

To monitor only one part of a web page in Fluxguard, configure an Inclusion Filter for the region you want to keep. Fluxguard removes the rest of the page from the DOM before monitoring. Start with an initial crawl, add the filter in Page Settings or Session Settings, select the region visually or with a CSS selector, save, and crawl again to confirm the result. See Fluxguard’s filtering documentation for the product’s current interface and details.

Set up an Inclusion Filter

1. Add the page and let its first crawl finish. This creates a baseline that you can use to check the filter.
2. Open the filter settings at the right scope. Use Page Settings for one page, Session Settings for pages in a session, or account-level settings if the same rule should apply across the account.
3. Choose Inclusion Filters. Select the region to keep with Visual Selector, or enter a CSS selector.
4. Save and run another crawl. Check that the intended region remains and unrelated content is removed.
5. Adjust and validate if needed. If the result is blank, the selector may not match. Inspect the current page, revise the selector, and crawl again.

Choose a selector that will last

Visual Selector lets you choose a region from a rendered view based on the initial crawl. It may not render every site accurately. If it selects the wrong area or cannot identify the region reliably, inspect the live page in your browser:

1. Right-click the target region and choose Inspect.
2. In Chrome DevTools, locate the element that contains the content you want monitored.
3. Right-click that element and choose Copy selector.
4. Review the copied selector in the Elements panel. Reduce unnecessary nesting and class details while keeping it specific enough to identify the intended region.
5. Use the selector in Fluxguard, save, and run a new crawl to confirm the match.

Prefer a simple selector based on a stable element or identifier. A long selector tied to several levels of page nesting or generated class names can stop matching after a redesign. Avoid overlapping filters where possible, and add one filter at a time so you can see its effect.

Inclusion, exclusion, and ignore rules

Rule	What happens	Use it when
Inclusion Filter	Keeps the matched region and removes the rest of the page from the DOM.	Only a specific region should remain in the monitored page.
Exclusion Filter	Removes matched regions from the DOM before capture.	The whole page matters except for noisy areas such as a header or sidebar.
Selector Ignore	Keeps the captured area but excludes it from HTML comparison. This is available with the HTML change detection strategy.	The content should remain in the capture but should not trigger an HTML change.
Selector Attribute Ignore	Ignores selected attributes, such as a changing class or style, during HTML comparison.	An attribute changes frequently but its changes are not meaningful to monitor.

These options are not interchangeable. Inclusion and exclusion filters alter the DOM before capture and can affect how the page renders. Selector Ignore preserves the captured area and changes what Fluxguard considers during HTML comparison. Multiple inclusion filters are allowed; Fluxguard says it stops checking further inclusion filters after one matches.

Scope the rule carefully

• Page scope: apply a filter to one page when its structure or monitoring goal is unique.
• Session scope: share a filter across pages in a session when the same selector and intent fit them all.
• Account scope: use account-level filters only when the rule should apply across the account.

A shared rule is easier to manage, but only use it where the selector matches the same meaningful region. A selector that works on one page may be absent or refer to a different part of another page.

When filters are not the right fix

Fluxguard recommends beginning without filters and adding them when false positives make them necessary. Each rule adds maintenance work. If most of the page is relevant and only a few parts are noisy, exclusions may fit. If more than five Exclusion Filters seem necessary, Fluxguard’s guidance suggests considering a smaller number of Inclusion Filters instead. Depending on the source of noise, change-detection strategy, Network Blocks, or Transforms may also address it.

Troubleshooting

Symptom	Likely cause	What to do
The filtered result is blank.	No Inclusion Filter selector matched the page.	Check the current page’s DOM, confirm the selector still matches, and run another crawl.
The wrong region remains.	The selector is too broad, or Visual Selector did not identify the intended element accurately.	Inspect the live page, choose a more specific stable element, and validate with a new crawl.
The filter stopped working after a site change.	The selector relied on nesting or classes that changed.	Inspect the updated DOM and replace the brittle selector with a simpler one that still identifies the region.
Other pages in the session are unexpectedly affected.	The filter was applied at session or account scope instead of page scope.	Review the settings scope and move the rule to Page Settings if it is meant for just one page.
Content disappears or the layout changes unexpectedly.	An Inclusion or Exclusion Filter removed DOM content that affected rendering.	Confirm the selector and rule type. If the content should stay in the capture but not count in HTML comparison, consider Selector Ignore where supported.
Changes in a class or style trigger alerts.	The attribute changes even when the content of interest does not.	Consider a Selector Attribute Ignore for the changing attribute, if HTML comparison is the relevant strategy.

Reliability and maintenance checklist

• Start with the initial crawl as your reference point.
• Keep the number of filters small and avoid overlapping rules.
• Use the narrowest scope that matches the intended pages.
• Check selectors against the current DOM, especially after page redesigns.
• Run another crawl after each filter change and verify both the retained region and removed content.
• If the monitored region becomes blank or shifts, revisit the selector before treating it as a content change.

Or skip the browser setup

If your goal is to capture a clean screenshot of a page region or full page, ScreenshotNeo is a website screenshot API and MCP server. It does not configure Fluxguard monitoring rules, but it can return a screenshot or PDF with one GET request. The API supports capturing an element by CSS selector, full-page capture, custom CSS and JavaScript, waits, and other capture options; see the ScreenshotNeo API documentation.

curl -G "https://api.screenshotneo.com/v1/shot" -d access_key=YOUR_API_KEY --data-urlencode url=https://stripe.com -o shot.webp

import requests

r = requests.get(
    "https://api.screenshotneo.com/v1/shot",
    params={"access_key": "YOUR_API_KEY", "url": "https://stripe.com"},
    timeout=90,
)
open("shot.webp", "wb").write(r.content)

const q = new URLSearchParams({ access_key: 'YOUR_API_KEY', url: 'https://stripe.com' });
const res = await fetch(`https://api.screenshotneo.com/v1/shot?${q}`);
if (!res.ok) throw new Error(`Screenshot request failed: ${res.status}`);
await Bun.write('shot.webp', res);

ScreenshotNeo removes cookie banners, newsletter popups, and chat widgets before the shot. Bot checks, blank pages, and failed loads are never billed. Its MCP server lets AI agents take screenshots, and 1,000 screenshots per month are free with no card; paid plans start at $5 for 3,000. Create a free ScreenshotNeo account.

FAQ

Can I monitor more than one region?

Fluxguard allows multiple Inclusion Filters. Validate the resulting crawl to confirm the regions you intend to keep.

Does Selector Ignore remove an area from the screenshot?

No. Selector Ignore is applied after capture and excludes matching content from HTML comparison. Inclusion and Exclusion Filters remove matching or surrounding content from the DOM before capture.

Should I add filters before the first crawl?

The documented workflow uses an initial crawl as a baseline. Fluxguard recommends starting without filters and adding them when false positives justify them.