fix(react): PostHogFeature should render fallback when flag doesn't exist#3146
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gustavohstrassburger merged 4 commits intomainfrom Feb 25, 2026
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…xist When a feature flag doesn't exist and no match is specified, PostHogFeature should render the fallback instead of the children. Previously, the component would incorrectly render children because undefined === undefined was true. Added guard to check if variant exists before evaluating match conditions. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>
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Size Change: +236 B (0%) Total Size: 6.16 MB
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Changes the condition from `if (variant)` to `if (variant !== undefined)`
to distinguish between undefined flags (should show fallback) and explicitly
false flags (can match against match={false}).
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>
marandaneto
reviewed
Feb 25, 2026
| {childNode} | ||
| </VisibilityAndClickTrackers> | ||
| ) | ||
| if (variant !== undefined) { |
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https://posthog.com/docs/libraries/js/usage#enriched-flag-analytics
anyone can pass any flag to PostHogFeature
how do we know if the flag actually exists?
it could that payload and variant are undefined here
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ah your last commit checks for variant
marandaneto
approved these changes
Feb 25, 2026
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dont forget to add a changeset and the label for releasing |
🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>
gustavohstrassburger
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Problem
The PostHogFeature component had incorrect behavior when a feature flag doesn't exist and no match is specified. Instead of rendering the fallback, it would incorrectly render the children content.
This bug occurred because the component only checked if the variant matched without first verifying if the variant exists at all.
Changes
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pnpm changesetto generate a changeset file