Cardmarket Chart Extension by Matras

This extension replaces the default Cardmarket chart with improved price and availability charts that become more accurate and more useful as the community grows.

What does it show?

📈 7-day average price (AVG7) for smoother price trends

📦 Available item count over time

⏱️ Multiple time ranges: 30 days, 1 year, max

Historical data on Cardmarket is limited.
This extension improves charts by collecting anonymized, aggregated market data contributed by users.

➡️ The more users participate, the better and more complete the charts become for everyone.

Optional features (recommended)

✅ Community data sharing – helps build better historical charts

✅ Random fetch – automatically collects live market data in the background while browsing

Both features are opt-in and can be enabled or disabled at any time.

Privacy-friendly by design

-No accounts required
-No tracking
-No personal data collected
-Only product-related numeric data (prices and availability)