Seems to be fruticose lichen but in bad shape. Found on sycamore tree on banks of canal. From lobes looks like Ramalina canariensis.
Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
No interactions present.
I don't think this would be identifiable, even with a sharp photograph. Immature, urban lichens are really not, in my opinion, worth any effort. Sorry.
Lat/Lng: 53.33264, -6.24966
OS grid ref: SG171901
Busy urban road along banks of Grand Canal in Dublin