What are the details and requirements for the E S Entry visa in Thailand, and how does it compare to visa exemption options for British passport holders?

The user recently received their E S Entry visa for Thailand with an intended stay of 89 days, noting a requirement for a selfie taken from a mobile device instead of a traditional photo booth. Several comments discuss the meaning of 'E S,' express skepticism about mobile selfies, and inquire about visa and entry exemptions for British passport holders, highlighting preferences for visas over exemptions and potential extensions.