Let's say this doesn't get updated I don't see a problem. It will continue to function as it is until it gets outdated and replaceed. Let's say it changes and does something evil, hopefully Google, Microsoft will catch the issue. If they don't someone will and people will stop trusting react or whatever product pulls these changes in.
Doing it yourself I would just freeze versions.
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In this case I find it odd for someone to keep maintanier status for a company repo they no longer work for 2 years after leaving.
I would have forked and introduced new changes in my own repo if I cared about the project. Let others follow if they desire new updates or force airbrb to assign someone to update. or better get airbrb to pay you to keep updating.
Lets just say someone at booking.com or tripping.com or some other hungry and less-that-totally-ethical AirBNB competitor works this out, and offers to buy the library or pay Zac $bignum in return for adding in some "additional analytics" aka industrial espionage allowing them to see searches/bookings made by users of apps with the library embedded.
Now Zac probably isn't the sort of person who'd do that, but once you get to a project like React which has 10,000 or so dependancies - surely _some_ of those dependancy authors would do that, for enough pieces of silver...
Doing it yourself I would just freeze versions.
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In this case I find it odd for someone to keep maintanier status for a company repo they no longer work for 2 years after leaving.
I would have forked and introduced new changes in my own repo if I cared about the project. Let others follow if they desire new updates or force airbrb to assign someone to update. or better get airbrb to pay you to keep updating.