Storybook and visual testing: Why testing isolated components is not enough
Storybook has become the standard for documenting and testing UI components. But for visual testing, testing isolated components is not enough.
Read more →Visual Testing — All Articles & Tutorials
156 articles
Visual testing is a quality assurance discipline that consists in automatically comparing the rendered output of an interface between two versions, to detect regressions invisible to classic functional tests. Where a unit test verifies that a function returns the right value, a visual test verifies that what the user sees stays consistent with what was intended.
This page gathers articles from the Delta-QA blog dedicated to visual testing across all its facets: comparison methods (pixel by pixel, perceptual, structural), market tools, integration into CI/CD pipelines, measurable ROI for QA teams. Whether you are discovering the discipline or seeking to industrialize your practice, you will find here the guides, comparisons and field feedback to move forward.
Delta-QA is a no-code visual testing tool, with an On-Premise option — the purpose of this blog is also to honestly share the strengths and limits of each approach, without hiding the trade-offs.
Selenium and visual testing: The complete guide for 2026
Visual testing with Selenium: screenshots, plugins, Applitools. Their limitations and why visual testing deserves a dedicated tool.
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What is a CSS regression? Definition, examples, and detection guide
CSS regression: unintentional appearance change after code modification. Why it's invisible in diffs and how to detect it effectively.
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QA manager: the strategic guide to automating regression testing in your team
QA manager guide: introduce automated regression testing, convince leadership, overcome resistance, train testers, measure success.
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Why your website looks different across browsers (and how to fix it)
Discover why Chrome, Firefox and Safari render your site differently. Rendering engines, non-standard CSS, fonts: understand the causes and apply concrete solutions.
Read more →Why your QA team needs automated regression testing (and probably already knows it)
UI bugs are up to 70% of bugs reported in production. Your QA team tests functionality, not the interface: how automated regression testing closes the gap.
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Playwright vs Puppeteer: Which tool for visual testing in 2026?
Playwright vs Puppeteer for regression testing: which to choose? Why a no-code tool can be a game changer. Complete comparison.
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Web performance and visual testing: CLS is a visual problem, not a functional one
Cumulative Layout Shift, FOUC, and broken lazy loading are visual problems that performance tests miss. Visual testing catches what metrics can't.
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Regression testing in a monorepo: How not to test 47 projects on every commit
Monorepo regression testing (Nx, Turborepo, Lerna): exploit dependency graph to test only affected projects, avoid 45-min pipelines.
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