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Preview of Fantasy Sync Assistant

Fantasy Sync Assistant by wazam

Syncs ESPN fantasy baseball transactions to a Fantrax mirrored league via the Fantrax Commissioner pages, keeping rosters current so the available trending players page reflects only what is available for quick and accurate free agent scouting.

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Screenshots
Extension popup on first open showing the queue, cutoff controls, and quick links before any transactions are loaded.ESPN Recent Activity page with transactions scraped into the queue. Cutoff range set to filter out older moves.Fantrax Commissioner page after the extension has automatically processed a batch of add/drop transactions.
About this extension
Github: https://github.com/wazam/fantasy-sync-extension/

Fantasy Sync Assistant is a Firefox extension for competitive fantasy baseball players who mirror their ESPN league on Fantrax. Fantrax's available trending players page becomes accurate only when your Fantrax rosters match ESPN exactly. This extension scrapes ESPN transactions and draft picks into a queue and replays each move on the Fantrax Commissioner pages, keeping your mirror up to date without manual re-entry.

Usage:
  1. Save your ESPN and Fantrax league IDs in the popup Quick Links section
  2. Navigate to an ESPN Recent Activity or Draft Recap page to scrape transactions into the queue
  3. Set the From / To cutoff range to narrow which transactions will be processed
  4. Open the Fantrax Commissioner page (Claim/Drop, Trade, or Draft Import) in the same browser tab
  5. Press F8 to process the entire queue automatically, or F7 to step through the next transaction one at a time

Features:
  • Transaction Queue -- scrapes transactions from ESPN Recent Activity and Draft Recap pages; processed transactions are marked with strikethrough and out-of-window transactions are shown in grey
  • Exclude Transactions -- Ctrl+click any queue row to skip it during processing; click again to restore it
  • Queue Controls -- search icon filters the queue by player name; reset icon marks all transactions as unprocessed; trash icon clears the entire queue
  • Cutoff Range -- From / To datetime fields define the window of transactions to process; click any queue row to set the lower bound instantly; drag across rows to set both bounds; paste ESPN-format timestamps like "Mon Apr 6 6:19 am" and they auto-convert to the correct format
  • Auto Run (F8) -- processes the entire transaction queue automatically, navigating between Fantrax pages as needed
  • Next (F7) -- processes one transaction on the current Fantrax tab; also stops auto-run while it is active
  • Transaction Types -- handles adds, drops, trades, and draft picks; searches for players by name with fallback variants for initials, accents, hyphens, and MLB team disambiguation
  • Quick Links -- ESPN and Fantrax league IDs can be saved by pasting a full league URL or just the extracted ID; one-click buttons open the corresponding league page once an ID is saved
  • Roster Size -- displays a recommended Fantrax max roster size that accounts for players who were on the Injured List at the time of an ESPN transaction but are healthy when replaying; set Fantrax's max roster size to this number to avoid roster-full errors

Issues and Feature Requests:

Report bugs, league setting problems, or feature requests by opening an issue on the GitHub repository.
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for fantasy.espn.com
  • Access your data for www.fantrax.com

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Add-on Links
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Version
1.1.2
Size
67.96 KB
Last updated
5 days ago (Apr 30, 2026)
Related Categories
  • Games & Entertainment
License
MIT License
Version History
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