[QA] [Mainnet] "Source chain gas estimate" value differs from gas estimate in MetaMask - ETH (Base)

[tsadovska]

Describe the current behavior in detail

Checked on https://preview.portalbridge.com/b05f4e9322/ [Mainnet] with macOS and Google Chrome.

Steps:

1. Prepare to send 0.001 USDC (Base) from Base (MetaMask) to Solana (Backpack)
2. Check "Source chain gas estimate" value in Preview section
3. Click on "Approve and proceed with transaction" button
4. Check gas estimate in MetaMask notification

Actual result:

• "Source chain gas estimate" value on wormhole-connect / Portal Bridge is ~ 0.0003 ETH (Base) (~$1.04)
• "Estimated fee" value in MetaMask is 0.00003182ETH (~$0.11)

What is the expected/desired behavior

Gas estimate on wormhole-connect/ Portal Bridge is similar to gas estimate in MetaMask notification.

[tsadovska]

Issue is also reproducible on https://preview.portalbridge.com/8228d00809/ [Mainnet].

• "Source chain gas estimate" value on Portal Bridge is ~ 0 ETH (Base) ($0.00)
• "Estimated fee" value in MetaMask is 0.0000169 ETH ($0.06)