syn case ignore
syn sync linebreaks=1
+let s:conceal = ''
+let s:concealends = ''
+if has('conceal')
+ let s:conceal = ' conceal'
+ let s:concealends = ' concealends'
+endif
+
"additions to HTML groups
-syn region htmlItalic start="\\\@<!\*\S\@=" end="\S\zs\\\@<!\*" keepend oneline
-syn region htmlItalic start="\(^\|\s\)\@<=_\|\\\@<!_\([^_]\+\s\)\@=" end="\S\@<=[^\\]_\|[^\\]_\S\@=" keepend oneline
-syn region htmlBold start="\S\zs\*\*\|\*\*\S\@=" end="\S\zs\*\*\|\*\*\S\@=" keepend oneline
-syn region htmlBold start="\S\zs__\|__\S\@=" end="\S\zs__\|__\S\@=" keepend oneline
-syn region htmlBoldItalic start="\S\zs\*\*\*\|\*\*\*\S\@=" end="\S\zs\*\*\*\|\*\*\*\S\@=" keepend oneline
-syn region htmlBoldItalic start="\S\zs___\|___\S\@=" end="\S\zs___\|___\S\@=" keepend oneline
+syn region htmlItalic start="\\\@<!\*\ze[^\\\*\t ]" end="[^\\\*\t ]\zs\*" keepend oneline
+syn region htmlItalic start="\\\@<!_\ze[^\\_\t ]" end="[^\\_\t ]\zs_" keepend oneline
+syn region htmlBold start="\*\*\ze\S" end="\S\zs\*\*" keepend oneline
+syn region htmlBold start="__\ze\S" end="\S\zs__" keepend oneline
+syn region htmlBoldItalic start="\*\*\*\ze\S" end="\S\zs\*\*\*" keepend oneline
+syn region htmlBoldItalic start="___\ze\S" end="\S\zs___" keepend oneline
" [link](URL) | [link][id] | [link][] | ![image](URL)
syn region mkdFootnotes matchgroup=mkdDelimiter start="\[^" end="\]"
-syn region mkdID matchgroup=mkdDelimiter start="\[" end="\]" contained oneline
-syn region mkdURL matchgroup=mkdDelimiter start="(" end=")" contained oneline
-syn region mkdLink matchgroup=mkdDelimiter start="\\\@<!!\?\[" end="\]\ze\s*[[(]" contains=@mkdNonListItem,@Spell nextgroup=mkdURL,mkdID skipwhite oneline
+execute 'syn region mkdID matchgroup=mkdDelimiter start="\[" end="\]" contained oneline' . s:conceal
+execute 'syn region mkdURL matchgroup=mkdDelimiter start="(" end=")" contained oneline' . s:conceal
+execute 'syn region mkdLink matchgroup=mkdDelimiter start="\\\@<!!\?\[" end="\]\ze[[(]" contains=@mkdNonListItem,@Spell nextgroup=mkdURL,mkdID skipwhite oneline' . s:concealends
" Autolink without angle brackets.
" mkd inline links: protocol optional user:pass@ sub/domain .com, .co.uk, etc optional port path/querystring/hash fragment
syntax region mkdInlineURL matchgroup=mkdDelimiter start="(\(https\?:\/\/\(\w\+\(:\w\+\)\?@\)\?\([A-Za-z][-_0-9A-Za-z]*\.\)\{1,}\(\w\{2,}\.\?\)\{1,}\(:[0-9]\{1,5}\)\?\S*)\)\@=" end=")"
" Autolink with angle brackets.
-syn region mkdInlineURL matchgroup=mkdDelimiter start="\\\@<!<\(\(https\?\|ftp\|git\|coap\|doi\|javascript\|aaas\?\|about\|acap\|cap\|cid\|crid\|data\|dav\|dict\|dns\|file\|geo\|go\|gopher\|h323\|iax\|icap\|im\|imap\|info\|ipp\|iris\|iris.beep\|iris.xpc\|iris.xpcs\|iris.lwz\|ldaps\?\|mailto\|mid\|msrp\|msrps\|mtqp\|mupdate\|news\|nfs\|ni\|nih\|nntp\|opaquelocktoken\|pop\|pres\|rtsp\|service\|session\|shttp\|sieve\|sip\|sips\|sms\|snmp,soap.beep\|soap.beeps\|tag\|tel\|telnet\|tftp\|thismessage\|tn3270\|tip\|tv\|urn\|vemmi\|wss\?\|xcon\|xcon-userid\|xmlrpc.beep\|xmlrpc.beeps\|xmpp\|z39.50r\|z39.50s\|adiumxtra\|afp\|afs\|aim\|apt,attachment\|aw\|beshare\|bitcoin\|bolo\|callto\|chrome,chrome-extension\|com-eventbrite-attendee\|content\|cvs,dlna-playsingle\|dlna-playcontainer\|dtn\|dvb\|ed2k\|facetime\|feed\|finger\|fish\|gg\|gizmoproject\|gtalk\|hcp\|icon\|ipn\|irc6\|ircs\?\|itms\|jar\|jms\|keyparc\|lastfm\|magnet\|maps\|market,message\|mms\|ms-help\|msnim\|mumble\|mvn\|notes\|oid\|palm\|paparazzi\|platform\|proxy\|psyc\|query\|res\|resource\|rmi\|rsync\|rtmp\|secondlife\|sftp\|sgn\|skype\|smb\|soldat\|spotify\|ssh\|steam\|svn\|teamspeak\|things\|udp\|unreal\|ut2004\|ventrilo\|view-source\|webcal\|wtai\|wyciwyg\|xfire\|xri\|ymsgr'\):\/\/[^> ]*>\)\@=" end=">"
+syn region mkdInlineURL matchgroup=mkdDelimiter start="\\\@<!<\ze[a-z][a-z0-9,.-]\{1,22}:\/\/[^> ]*>" end=">"
" Link definitions: [id]: URL (Optional Title)
syn region mkdLinkDef matchgroup=mkdDelimiter start="^ \{,3}\zs\[" end="]:" oneline nextgroup=mkdLinkDefTarget skipwhite