Error executing process > 'output_documentation'

Caused by:
  Process `output_documentation` terminated with an error exit status (255)

Command executed:

  markdown_to_html.r output.md results_description.html

Command exit status:
  255

Command output:
  (empty)

Command error:
  ERROR  : Unknown image format/type: /camp/lab/luscomben/working/chris/projects/nf/2020-nucleosome-occupancy-pred/henikoff_2019/work/singularity/nfcore-mnaseseq-dev.img
  ABORT  : Retval = 255