To the many people who have been identifying unknown lichens as genus Lichen: it has recently been brought to my attention that the genus Lichen has not been in use for some time and is synonymous with Parmelia (details), so I'm retiring it. In the future you should identify any unknown lichens as kingdom Fungi. I know that's not very specific, but lichens as a group do not conform to any one taxon: they do not all share a common ancestor because lichenization (probably) evolved numerous times. It's sort of like trying to identify a tall, woody plant as a "tree": linguistically accurate, but not taxonomically meaningful. Some day we might develop non-taxonomic categorization schemes for iNat, but until we do, identifying unknown lichens as Fungi is the way to go.
That being said, a quick search on Index Fungorum reveals numerous species in the genus Lichen that are considered synonyms of species outside of genus Parmelia, so in favor of extreme taxonomic conservatism and to correct all the misidentified Lichen observations, I'm just swapping Lichen into Fungi.
Unintended disagreements occur when a parent (B) is
thinned by swapping a child (E) to another part of the
taxonomic tree, resulting in existing IDs of the parent being interpreted
as disagreements with existing IDs of the swapped child.
Identification
ID 2 of taxon E will be an unintended disagreement with ID 1 of taxon B after the taxon swap
If thinning a parent results in more than 10 unintended disagreements, you
should split the parent after swapping the child to replace existing IDs
of the parent (B) with IDs that don't disagree.
I agree, the genus Lichen thing is very confusing to non Lichen experts