Unable to upload GPX files

Hi, all,

Not sure if this is a glitch which has arisen, but I'm suddenly unable to upload GPX files to use them in cycle.travel. I browse to the GPX file on my desk top and give it a title. When I select 'start upload' I get a page with 'Choose a Track - Upload'. I select 'Upload' (don't recall that step previously, but that may be my poor memory). Then, after thinking about it for a little while, I'm told: 'Sorry. The task failed because of an error: undefined method `css' for nil:NilClass'. I don't know what that means, but I can upload the GPX files onto other web pages (Komoot, for example), so it doesn't seem to be the GPX file that's corrupted.