COMC Purchase History Helper

Local purchase-history CSV import and badges on verified COMC page layouts.

Check whether you have purchased a card before while browsing COMC. COMC Purchase History Helper is an unofficial Chrome extension that uses a manually imported purchase-history CSV to display Purchased badges on COMC listings and product pages. Imported records remain available after cards have been shipped out of Inventory. Features • Import a purchase-history CSV after reviewing a preview. • Reimport the same purchase records without adding duplicates. • See purchase-history badges on listings and product pages. • Search history by card type and inspect purchase dates, USD prices and other record details. • Export and restore JSON backups. • Choose Automatic, Japanese or English for the interface. Supported views Supports Details, List and Text. Thumbs is not supported. Listing size, sorting, pagination, filters and sport do not impose fixed restrictions. Graded cards are matched by card type. Missing product information or an unsupported page structure will not be treated as a confirmed purchase match. Getting started 1. Manually download your purchase-history CSV from COMC. 2. Open the extension's Import, history & backup page and select the CSV. 3. Review and confirm the import, then open a supported COMC page. Import an updated CSV after making new purchases. There is no automatic synchronization. How your data is handled The selected CSV is read within Chrome. After confirmation, purchase records and settings are saved in this Chrome profile. Displayed public product information and URLs are processed locally to match your imported history. The extension does not send your history to external servers, use analytics or sync it to the cloud. Stored data and JSON backups are not encrypted. The status in a badge added to a COMC page may be visible to that page's scripts. Badges can be turned off in Settings. Page badges do not contain purchase dates, prices, record counts or purchased ItemIDs. Before you use it • A badge indicates purchase history for the same card type. It does not guarantee current ownership, the same physical item, or the same grading company, grade or condition. • Return flags, conflicts and uncertain matches are marked for review. No badge is not proof that a card has never been purchased. • Results cover only the records in your imported CSV files. Dates retain the CSV's recorded values without timezone conversion. • CSV files must be UTF-8, with a maximum of 10 MiB and 5,000 rows per file. The local history supports up to 5,000 purchase records, subject to storage size limits. • History remains in this Chrome profile after you log out of COMC. Removing the extension deletes its local history; export a backup when needed. • The extension does not log in to COMC, crawl pages, make purchases, modify carts or make offers. This is an unofficial extension, with no affiliation with or endorsement by COMC. Developer: Takumetal Support: X @takumetal55 by DM, reply or mention https://x.com/takumetal55 Privacy policy: https://takumetal.github.io/comc-purchase-history-helper-privacy/privacy-en.html