[beta] Backports (#5299)

* Fix FireFox overflows (#5000)

* Max width for container

* Set min-width

* Switching ValidatorSet (#4961)

* add multi validator set

* nicer comment

* validate in constructor

* reporting

* Avoid clogging up tmp when updater dir has bad permissions. (#5024)

* force earliest era set in snapshot restore (#5021)

* v1.6.5

* Fine grained snapshot chunking

* Ropsten revival