It came to my attention that no one published a user defined language mode for Notepad++ that would allow you to view BB code tags in the editor relatively comfortably, so I decided to correct that omission by publishing mine.

As far as technical details go, there isn't anything of particular complexity here - various tags are defined as delimiters and URLs use the same trick that the built-in Markdown UDL uses.

Download UDL

Alternatively, raw UDL XML:

<NotepadPlus>
    <UserLang name="BB Code" ext="" udlVersion="2.1">
        <Settings>
            <Global caseIgnored="yes" allowFoldOfComments="no" foldCompact="no" forcePureLC="0" decimalSeparator="0" />
            <Prefix Keywords1="yes" Keywords2="no" Keywords3="no" Keywords4="no" Keywords5="no" Keywords6="no" Keywords7="no" Keywords8="no" />
        </Settings>
        <KeywordLists>
            <Keywords name="Comments"></Keywords>
            <Keywords name="Numbers, prefix1"></Keywords>
            <Keywords name="Numbers, prefix2"></Keywords>
            <Keywords name="Numbers, extras1"></Keywords>
            <Keywords name="Numbers, extras2"></Keywords>
            <Keywords name="Numbers, suffix1"></Keywords>
            <Keywords name="Numbers, suffix2"></Keywords>
            <Keywords name="Numbers, range"></Keywords>
            <Keywords name="Operators1">&quot;</Keywords>
            <Keywords name="Operators2"></Keywords>
            <Keywords name="Folders in code1, open"></Keywords>
            <Keywords name="Folders in code1, middle"></Keywords>
            <Keywords name="Folders in code1, close"></Keywords>
            <Keywords name="Folders in code2, open"></Keywords>
            <Keywords name="Folders in code2, middle"></Keywords>
            <Keywords name="Folders in code2, close"></Keywords>
            <Keywords name="Folders in comment, open"></Keywords>
            <Keywords name="Folders in comment, middle"></Keywords>
            <Keywords name="Folders in comment, close"></Keywords>
            <Keywords name="Keywords1">http:// https:// mailto: ftp:// ftps://</Keywords>
            <Keywords name="Keywords2"></Keywords>
            <Keywords name="Keywords3"></Keywords>
            <Keywords name="Keywords4"></Keywords>
            <Keywords name="Keywords5"></Keywords>
            <Keywords name="Keywords6"></Keywords>
            <Keywords name="Keywords7"></Keywords>
            <Keywords name="Keywords8"></Keywords>
            <Keywords name="Delimiters">00[quote 01 02[/quote] 03[spoiler 04 05[/spoiler] 06[code 07 08[/code] 09[b] 10 11[/b] 12[i] 13 14[/i] 15[b] 15[i] 16 17[/b] 17[/i] 18[h1] 18[h2] 18[h3] 19 20[/h1] 20[/h2] 20[/h3] 21[ 22 23]</Keywords>
        </KeywordLists>
        <Styles>
            <WordsStyle name="DEFAULT" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="COMMENTS" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="LINE COMMENTS" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="NUMBERS" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS1" fgColor="FF0080" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS2" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS3" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS4" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS5" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS6" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS7" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS8" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="OPERATORS" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="FOLDER IN CODE1" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="FOLDER IN CODE2" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="FOLDER IN COMMENT" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS1" fgColor="008040" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="254" />
            <WordsStyle name="DELIMITERS2" fgColor="808080" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS3" fgColor="0078AA" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS4" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="1" nesting="160" />
            <WordsStyle name="DELIMITERS5" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="2" nesting="160" />
            <WordsStyle name="DELIMITERS6" fgColor="000000" bgColor="FFFFFF" fontName="" fontStyle="3" nesting="0" />
            <WordsStyle name="DELIMITERS7" fgColor="0078AA" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS8" fgColor="0000FF" bgColor="FFFFFF" fontName="" fontStyle="0" nesting="16778240" />
        </Styles>
    </UserLang>
</NotepadPlus>

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