不能显示流程图

[Amazer]

st=>start: Start
e=>end
op=>operation: My Operation
cond=>condition: Yes or No?

st->op->cond
cond(yes)->e
cond(no)->op

但是并未显示流程图，应该怎么办？

[iamcco]

试下这个 pr 有时间我会测试合并 https://github.com/iamcco/markdown-preview.vim/pull/35