Also, I have found that if the PDF is large enough or complex enough, your TiddlyWiki document will crash and burn. Small simple PDFs embed quite nicely.
A work-around that is a safer bet is to make a tiddler that is an external link to the document. It can be a relative file:// type link so you can keep everything in one directory tree. Then you can do all the transcluding/tagging/etc. that you can do if it was embedded without the crashiness.
I Frankensteined together a little helper tiddler from tips and tricks from people here to make these external links that I include as a tool in each document I create ... cut and paste the following into a tiddler and start linking.
/Mike
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\define theTiddler() $(the_tiddler)$!!title
\define myconcat() $(t1)$$(t2)$
|!Filename |<$edit-text tiddler="$:/temp/ExternalLink" placeholder="filename" tag="input" type="text"/> |
|!Directory |<$edit-text tiddler="$:/temp/ExternalLink" field="directory" placeholder="directory" tag="input" type="text"/> |
''Filetype:'' <$select tiddler='$:/temp/ExternalLink' field='type' default='image/gif'>
<$list filter='[all[shadows+tiddlers]prefix[$:/language/Docs/Types/]each[group]sort[group]]'>
<optgroup label={{!!group}}>
<$list filter='[all[shadows+tiddlers]prefix[$:/language/Docs/Types/]group{!!group}] +[sort[description]]'>
<option value={{!!name}}><$view field='description'><$view field='title'/></$view> (<$view field='name'/>)</option>
</$list>
</optgroup>
</$list>
</$select>
<$set name="t1" value={{$:/temp/ExternalLink!!directory}}>
<$set name="t2" value={{$:/temp/ExternalLink!!text}}>
_canonical_uri field = <<myconcat>>
<$reveal type="nomatch" text="" state="$:/temp/ExternalLink">
<$reveal type="match" text={{$:/temp/ExternalLink}} state={{$:/temp/ExternalLink}}>
<$button set="$:/temp/ExternalLink!!title" setTo={{$:/temp/ExternalLink}}>
<$action-setfield $tiddler="$:/temp/ExternalLink" $field="_canonical_uri" $value=<<myconcat>>/>
Modify
</$button>
<$set name="the_tiddler" value={{$:/temp/ExternalLink}}>
<$button setTo="$:/temp/ExternalLink" set=<<theTiddler>>>
Fetch
</$button>
</$set>
</$reveal>
<$reveal type="match" text="" state={{$:/temp/ExternalLink}}>
<$button set="$:/temp/ExternalLink!!title" setTo={{$:/temp/ExternalLink}}>
<$action-setfield $tiddler="$:/temp/ExternalLink" $field="_canonical_uri" $value=<<myconcat>>/>
Create
</$button>
</$reveal>
</$reveal>
</$set>
</$set>
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