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OES_draw_buffers_indexed
WebGL Extension
WebGL2
Fingerprinting Signal
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What is OES_draw_buffers_indexed?
The OES_draw_buffers_indexed extension is part of the WebGL API and enables different blend options when writing to multiple color buffers simultaneously. Provides blendEquationiOES(), blendFunciOES(), colorMaskiOES(), enableiOES(), and disableiOES() methods for per-buffer blend control. Available in WebGL2 only.
Read MDN DocumentationBrowser Support
Checking Extension Support
This extension is part of the WebGL2 specification.
Browser support varies based on:
- Graphics card model and capabilities
- GPU driver version
- Browser version and vendor
- Operating system
Usage in Web Scraping & Anti-Bot Bypass
Modern anti-bot systems verify WebGL extensions to detect automated browsers. Mismatches between GPU hardware and available extensions are strong bot signals.
What Anti-Bot Systems Check:
- Extension availability: Does the reported GPU support these extensions?
- Extension combinations: Are the extensions typical for this GPU model?
- Consistency checks: Do reported extensions match other GPU signals?
- Missing extensions: Are expected extensions for this GPU absent?
Scrapfly's Anti-Scraping Protection (ASP)
Scrapfly automatically manages WebGL fingerprint consistency, ensuring all extensions
match the emulated GPU profile. This prevents detection by anti-bot systems that verify WebGL data.
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