A save wrote `trackedTokens` whole, so two pages on one network dropped each other's adds and brought back each other's removals. A save that keeps the network now merges this page's change into the stored list by contract address. A save that switches networks is unchanged. `mergeTrackedTokens()` does that merge, and the two other merges of tracked tokens now call it. It keeps one record per contract address, this page's for a token both lists hold, so a token held twice no longer multiplies. Model: opus-5-5