Description

Linea seems to be taking longer than other chains to process the approve transaction after it is submitted, so the trade transaction is erroring. This PR adds a hacky workaround where we artificially delay if we're on Linea to give the trade transaction more time. In the future, we'd want to avoid this hack, but for now it should increase the swap success rate on Linea.

With the delay, the token symbol also wasn't immediately populating on the awaiting swap page, so this PR also updates how it's retrieved.

Related issues

Fixes: #27804

Manual testing steps

1. Start a swap on Linea with a token that you have not granted approval for
2. Observe that the swap does not fail

Screenshots/Recordings

Before

After

Pre-merge author checklist

• I've followed MetaMask Contributor Docs and MetaMask Extension Coding Standards.
• I've completed the PR template to the best of my ability
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format if applicable
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Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.