MetaMask / MetaMask/metamask-extension
[Bug]: MetaMask fee estimation fails on non-EIP-1559 networks (missing suggestedMaxPriorityFeePerGas) causing pending txs and broken UI
Open
@jpuri is already working on this.
Since Feb 3, 2026.
area-gas
external-contributor
Gas
INVALID-ISSUE-TEMPLATE
regression-prod-13.4.3
Sev2-normal
team-confirmations
type-bug
- Dominant language
- TypeScript
- Stars
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Description
Describe the bug
On non-EIP-1559 EVM chains (e.g. Core DAO), MetaMask attempts to read and use EIP-1559 fee fields such as suggestedMaxPriorityFeePerGas. Since these fields are not supported by the network RPC, the value is undefined, which causes MetaMask’s fee estimation logic and UI to break.
Steps to reproduce
Attach screenshot showing error:
Cannot read properties of undefined (reading 'suggestedMaxPriorityFeePerGas')
Error messages or log output
Where was this bug found?
Live version (from official store)
Version
13.4.3
Build type
None
Browser
Chrome
Operating system
MacOS
Contributor guide
First steps
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Assessment
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