Could you check why this requires to use "\n" (single backslash for the line feed):
1. http://www.plantuml.com/plantuml/uml/SoWkIImgAStDuShBJqbLK0fo3et9gr7mJ4jCJbMeKGYfB01HBb3QDxy8I84L106voVbv9KNvEK0M4474WVeLd4fBIlBpYe5YCAIaa5YiK9HSgb3DfG07GEsv1VbvgNab2ag9O1M9gFArN33Q8JKl1UX60000
while this requires double backslash for the line feed:
2. http://www.plantuml.com/plantuml/uml/SoWkIImgAStDuShBJqbLK0fo3es9oQjHy4nBJ4vLg548gIm0KIvGsZU_24X1L0G1-SdvUIL5-Jb05X119O16A3YLbfJavnK31M58II6nMA4ekLIXcai136gv75BpKe0s0m00
(the only thing that changed is that in the later case i have removed the inner component)
The same issue observed intermittently for different types of components and depending on some other strange things as whether those contain links within the name or not, whether those contain inner elements or not, etc.
The problem is that there is no consistent rule on whether one must use "\n" or "\\n" since plantuml obviously behaves "unpredictably" differently. For instance, the example 1 above fails if you use "\\n": http://www.plantuml.com/plantuml/uml/SoWkIImgAStDuShBJqbLK0fo3es9oQjHy4nBJ4vLg548gIm0KIvGsZU_24X1L0G1-SdvUIL5-Jb05X119O16A3YLbfJavnK31M58II6nMA4ekLIXcai13e3wSmloyrBpIXIK4i4g4b7bQxbWj4DgNWhGcG00
while example 2 works ok with "\\n" and vice versa.