Jalview fails to load MUSCLE relaxed Clustal output

Using MUSCLE v3.8.31, a command line this will produce a Clustal-like alignment which Jalview 2.10.1 fails to load:

$ muscle -in example.fasta -clw -out example.aln
$ head -n 1 example.aln
MUSCLE (3.8) multiple sequence alignment

Using Muscle's strict Clustal alignment mode works:

$ muscle -in example.fasta -clwstrict -out example.aln
$ head -n 1 example.aln
CLUSTAL W (1.81) multiple sequence alignment