The result of toString on a number can be different across browsers for large numbers. In particular, it's possible for IE to use exponential notation, which was breaking Mnemonic._entropyChecksum.
This can be reproduced using this seed: patrol wise idea oyster inquiry crash dignity chronic scatter time admit pet, which is valid on Chrome and Firefox, but invalid on IE11 and Edge.
The result of toString on a number can be different across browsers for large numbers. In particular, it's possible for IE to use exponential notation, which was breaking Mnemonic._entropyChecksum.
This can be reproduced using this seed:
patrol wise idea oyster inquiry crash dignity chronic scatter time admit pet, which is valid on Chrome and Firefox, but invalid on IE11 and Edge.