I honestly think the (British) Liberal Democrats are in trouble.
Despite great local results on a national level they’re showing signs of not recovering from coalition
1. the Liberal Democrats were never a "mighty" party - they were a third party that gained significant popularity from opposing an unpopular Labour government from the left only to piss it all (and more) away by going into coalition with the Tories
2. Their local government performance is also hardly "great" - they gained a negligible number of councillors in 2016 and 2018 and actually lost councilllors in 2017 compared to what were very bad County Council elections for them four years earlier. In terms of vote share they showed increases in 2016 and 2017 (those 2017 losses were admittedly mainly because of the very high Tory position more than anything) but in 2018 their share fell again and isn't showing signs of revival. They're polling dramatically lower than any local government results in an incredibly long time - probably the dark old days post-merger in the late 80s and before that you're probably talking fifty years earlier as a comparably bad time - and aren't making many meaningful gains even compared to local elections where they did terrible under the Coalition.
When it comes to devolved legislatures there isn't any growth their either; there is a single Welsh Liberal Democrat in the Welsh Assembly (Wales being the former home of Liberalism and a place where in their darkest days they could still rely on for support) and in Scotland they went nowhere in 2016 and actually ended up finishing fifth behind the Greens for the first time . In London they also moved backwards - their Mayoral candidate finished fourth (behind the Greens) and lost her Deposit and in the Assembly lost one of their two seats and ended up fifth - behind the Greens as well as UKIP. So basically they've shown little evidence of any revival anywhere at a local level as well - sure you can point towards certain local election results and cherrypick local by-elections but everyone can do that: the Greens have gained seats in local by-elections in the last year despite clearly having moved backwards in recent years.