else
let s:oneline = ' oneline'
endif
-execute 'syn region htmlItalic start="\%(^\|\s\)\zs\*\ze[^\\\*\t ]\%(\%([^*]\|\\\*\|\n\)*[^\\\*\t ]\)\?\*\_W" end="[^\\\*\t ]\zs\*\ze\_W" keepend' . s:oneline
-execute 'syn region htmlItalic start="\%(^\|\s\)\zs_\ze[^\\_\t ]" end="[^\\_\t ]\zs_\ze\_W" keepend' . s:oneline
-execute 'syn region htmlBold start="\%(^\|\s\)\*\*\ze\S" end="\S\zs\*\*" keepend' . s:oneline
-execute 'syn region htmlBold start="\%(^\|\s\)\zs__\ze\S" end="\S\zs__" keepend' . s:oneline
-execute 'syn region htmlBoldItalic start="\%(^\|\s\)\zs\*\*\*\ze\S" end="\S\zs\*\*\*" keepend' . s:oneline
-execute 'syn region htmlBoldItalic start="\%(^\|\s\)\zs___\ze\S" end="\S\zs___" keepend' . s:oneline
+syn region mkdItalic matchgroup=mkdItalic start="\%(\*\|_\)" end="\%(\*\|_\)"
+syn region mkdBold matchgroup=mkdBold start="\%(\*\*\|__\)" end="\%(\*\*\|__\)"
+syn region mkdBoldItalic matchgroup=mkdBoldItalic start="\%(\*\*\*\|___\)" end="\%(\*\*\*\|___\)"
+execute 'syn region htmlItalic matchgroup=mkdItalic start="\%(^\|\s\)\zs\*\ze[^\\\*\t ]\%(\%([^*]\|\\\*\|\n\)*[^\\\*\t ]\)\?\*\_W" end="[^\\\*\t ]\zs\*\ze\_W" keepend' . s:oneline . s:concealends
+execute 'syn region htmlItalic matchgroup=mkdItalic start="\%(^\|\s\)\zs_\ze[^\\_\t ]" end="[^\\_\t ]\zs_\ze\_W" keepend' . s:oneline . s:concealends
+execute 'syn region htmlBold matchgroup=mkdBold start="\%(^\|\s\)\zs\*\*\ze\S" end="\S\zs\*\*" keepend' . s:oneline . s:concealends
+execute 'syn region htmlBold matchgroup=mkdBold start="\%(^\|\s\)\zs__\ze\S" end="\S\zs__" keepend' . s:oneline . s:concealends
+execute 'syn region htmlBoldItalic matchgroup=mkdBoldItalic start="\%(^\|\s\)\zs\*\*\*\ze\S" end="\S\zs\*\*\*" keepend' . s:oneline . s:concealends
+execute 'syn region htmlBoldItalic matchgroup=mkdBoldItalic start="\%(^\|\s\)\zs___\ze\S" end="\S\zs___" keepend' . s:oneline . s:concealends
" [link](URL) | [link][id] | [link][] | ![image](URL)
syn region mkdFootnotes matchgroup=mkdDelimiter start="\[^" end="\]"
syn match mkdCode /^\s*\n\(\(\s\{8,}[^ ]\|\t\t\+[^\t]\).*\n\)\+/
syn match mkdCode /\%^\(\(\s\{4,}[^ ]\|\t\+[^\t]\).*\n\)\+/
syn match mkdCode /^\s*\n\(\(\s\{4,}[^ ]\|\t\+[^\t]\).*\n\)\+/ contained
-syn match mkdListItem /^\s*\%([-*+]\|\d\+\.\)\s\+/ contained
+syn match mkdListItem /^\s*\%([-*+]\|\d\+\.\)\ze\s\+/ contained
syn region mkdListItemLine start="^\s*\%([-*+]\|\d\+\.\)\s\+" end="$" oneline contains=@mkdNonListItem,mkdListItem,@Spell
syn region mkdNonListItemBlock start="\(\%^\(\s*\([-*+]\|\d\+\.\)\s\+\)\@!\|\n\(\_^\_$\|\s\{4,}[^ ]\|\t+[^\t]\)\@!\)" end="^\(\s*\([-*+]\|\d\+\.\)\s\+\)\@=" contains=@mkdNonListItem,@Spell
syn match mkdRule /^\s*\*\s\{0,1}\*\s\{0,1}\*$/