* Supported Node Versions were set to match the [node release schedule](https://nodejs.org/en/about/releases/) which at the time of writing includes Node 12.x, 14.x, 16.x and 17.x
* The `yargs` dependecy was updated to `^17.2.1` to mitigate a security issue.
* The Showdown Licesnse has been changed from BSD-3-Clause to MIT
### Bug Fixes
* allow escaping of colons ([25c4420](https://github.com/showdownjs/showdown/commit/25c4420))
Version 1.9.0 introduces a new feature, the Markdown to HTML converter. This feature is still experimental and is a partial backport of the new Reverse Converter planned for version 2.0.
* **underline:** fix issue with consecutive spans ([81edc70](https://github.com/showdownjs/showdown/commit/81edc70))
### Features
* **converter.makeMarkdown:** [EXPERIMENTAL] add an HTML to MD converter ([e4b0e69](https://github.com/showdownjs/showdown/commit/e4b0e69)), closes [#388](https://github.com/showdownjs/showdown/issues/388) [#233](https://github.com/showdownjs/showdown/issues/233)
* **gfm-codeblocks:** add support for spaces before language declaration ([24bf7b1](https://github.com/showdownjs/showdown/commit/24bf7b1)), closes [#569](https://github.com/showdownjs/showdown/issues/569)
leading space no longer breaks gfm codeblocks ([828c32f](https://github.com/showdownjs/showdown/commit/828c32f)), closes [#523](https://github.com/showdownjs/showdown/issues/523)
* **images:** fix js error when using image references ([980e702](https://github.com/showdownjs/showdown/commit/980e702)), closes [#585](https://github.com/showdownjs/showdown/issues/585)
* **literalMidWordAsterisks:** now parses single characters enclosed by * correctly ([fe70e45](https://github.com/showdownjs/showdown/commit/fe70e45)), closes [#478](https://github.com/showdownjs/showdown/issues/478)
* **mentions:** allow for usernames with dot, underscore and dash ([dfeb1e2](https://github.com/showdownjs/showdown/commit/dfeb1e2)), closes [#574](https://github.com/showdownjs/showdown/issues/574)
* **nbsp:** fix replacing of nbsp with regular spaces ([8bc1f42](https://github.com/showdownjs/showdown/commit/8bc1f42))
* **completeHTMLDocument:** add option to output a complete HTML document ([a8427c9](https://github.com/showdownjs/showdown/commit/a8427c9))
* **metadata:** add support for embedded metadata ([63d949f](https://github.com/showdownjs/showdown/commit/63d949f)), closes [#260](https://github.com/showdownjs/showdown/issues/260)
* **tables:** raw html inside code tags in tables no longer breaks tables ([4ef4c5e](https://github.com/showdownjs/showdown/commit/4ef4c5e)), closes [#471](https://github.com/showdownjs/showdown/issues/471)
* **literalMidWordAsterisks:** no longer treats colon as alphanumeric char ([21194c8](https://github.com/showdownjs/showdown/commit/21194c8)), closes [#461](https://github.com/showdownjs/showdown/issues/461)
* **spanGamut:** code spans are hashed after parsing ([f4f63c5](https://github.com/showdownjs/showdown/commit/f4f63c5)), closes [#464](https://github.com/showdownjs/showdown/issues/464)
* **tables:** pipe character in code spans no longer breaks table ([0c933a0](https://github.com/showdownjs/showdown/commit/0c933a0)), closes [#465](https://github.com/showdownjs/showdown/issues/465)
* **openLinksInNewWindow:** hash links are not affected by the option ([11936ec](https://github.com/showdownjs/showdown/commit/11936ec)), closes [#457](https://github.com/showdownjs/showdown/issues/457)
* **package:** update yargs to version 10.0.3 ([#447](https://github.com/showdownjs/showdown/issues/447)) ([906b26d](https://github.com/showdownjs/showdown/commit/906b26d))
* **autolinks:** prevent _ and * to be parsed in links ([61929bb](https://github.com/showdownjs/showdown/commit/61929bb)), closes [#444](https://github.com/showdownjs/showdown/issues/444)
### Features
* **ellipsis:** add auto-ellipsis support ([25f1978](https://github.com/showdownjs/showdown/commit/25f1978))
- *Example:*
input
```md
this is an ellipsis...
```
output
```html
<p>this is an ellipsis…</p>
```
* **emoji:** add emoji support through option `emoji`([5b8f1d3](https://github.com/showdownjs/showdown/commit/5b8f1d3)), closes [#448](https://github.com/showdownjs/showdown/issues/448)
- *Usage:*
```js
var conv = new showdown.Converter({emoji: true});
```
- *Example:*
input
```md
this is a smile :smile: emoji
```
output
```html
<p>this is a smile 😄 emoji</p>
```
* **start ordered lists at an arbitrary number:** add support for defining the first item number of ordered lists ([9cdc35e](https://github.com/showdownjs/showdown/commit/9cdc35e)), closes [#377](https://github.com/showdownjs/showdown/issues/377)
- *Example:*
input
```md
3. foo
4. bar
5. baz
```
output
```html
<olstart="3">
<li>foo</li>
<li>bar</li>
<li>baz</li>
</ol>
```
* **underline:** add EXPERIMENTAL support for underline ([084b819](https://github.com/showdownjs/showdown/commit/084b819)), closes [#450](https://github.com/showdownjs/showdown/issues/450)
- *Usage:*
```js
var conv = new showdown.Converter({underline: true});
```
- *Example:*
input
```md
this is __underlined__ and this is ___also underlined___
```
output
```html
<p>this is <u>underlined</u> and this is <u>also underlined</u></p>
```
- *Note:* With this option enabled, underscore no longer parses as `<em>` or `<strong>`
### BREAKING CHANGES
* start ordered lists at an arbitrary number: Since showdown now supports starting ordered lists at an arbitrary number,
* **tables:** tables are properly rendered when followed by a single linebreak and a list ([d88b095](https://github.com/showdownjs/showdown/commit/d88b095)), closes [#443](https://github.com/showdownjs/showdown/issues/443)
* **html-comments:** changed regex to prevent malformed long comment to freeze showdown ([3efcd10](https://github.com/showdownjs/showdown/commit/3efcd10)), closes [#439](https://github.com/showdownjs/showdown/issues/439)
* **loader:** allow AMD loader to be used within Node env ([ff24bdb](https://github.com/showdownjs/showdown/commit/ff24bdb))
### Features
* **base64-wrapping:** support for wrapping base64 strings ([8c593a4](https://github.com/showdownjs/showdown/commit/8c593a4)), closes [#429](https://github.com/showdownjs/showdown/issues/429)
* **literalMidWordAsterisks:** option no longer treats punctuation as word character ([8f05be7](https://github.com/showdownjs/showdown/commit/8f05be7)), closes [#398](https://github.com/showdownjs/showdown/issues/398)
* **tables:** allow for one column table ([fef110c](https://github.com/showdownjs/showdown/commit/fef110cccb2d02b218183398d9baa0ae256a7283)), closes [#406](https://github.com/showdownjs/showdown/issues/406)
* **rawHeaderId:** Remove only spaces, ' and " from generated header ids ([1791cf0](https://github.com/showdownjs/showdown/commit/1791cf0)), closes [#409](https://github.com/showdownjs/showdown/issues/409)
* **rawPrefixHeaderId:** add option to prevent showdown from modifying the prefix ([ff26c08](https://github.com/showdownjs/showdown/commit/ff26c08)), closes [#409](https://github.com/showdownjs/showdown/issues/409)
* **githubMentions:** githubMentions now works with openLinksInNewWindow options ([1194d88](https://github.com/showdownjs/showdown/commit/1194d88)), closes [#403](https://github.com/showdownjs/showdown/issues/403)
* **lists:** fix multi paragraph lists with sublists ([a2259c0](https://github.com/showdownjs/showdown/commit/a2259c0)), closes [#397](https://github.com/showdownjs/showdown/issues/397)
* **tablesHeaderId:** fix mismatch of option name ([51e4693](https://github.com/showdownjs/showdown/commit/51e4693)), closes [#412](https://github.com/showdownjs/showdown/issues/412)
* **HTML Parser:** fix nasty bug where malformed HTML would hang showdown ([6566c72](https://github.com/showdownjs/showdown/commit/6566c72)), closes [#393](https://github.com/showdownjs/showdown/issues/393)
* **anchors:** fix issue with brackets in link URL ([7ba18dd](https://github.com/showdownjs/showdown/commit/7ba18dd)), closes [#390](https://github.com/showdownjs/showdown/issues/390)
* **excludeTrailingPunctuationFromURL:** add comma to punctuation list ([fa35fd5](https://github.com/showdownjs/showdown/commit/fa35fd5)), closes [#354](https://github.com/showdownjs/showdown/issues/354)
* **excludeTrailingPunctuationFromURLs:** fix weird character when this option with simplifiedAutoLinks ([71acff5](https://github.com/showdownjs/showdown/commit/71acff5)), closes [#378](https://github.com/showdownjs/showdown/issues/378)
* **HTML parsing:** fix HTML parsing issues with nested tags ([6fbc072](https://github.com/showdownjs/showdown/commit/6fbc072)), closes [#357](https://github.com/showdownjs/showdown/issues/357) [#387](https://github.com/showdownjs/showdown/issues/387)
* **openLinksInNewWindow:** encode _ to prevent clash with em ([813f832](https://github.com/showdownjs/showdown/commit/813f832)), closes [#379](https://github.com/showdownjs/showdown/issues/379)
* **package:** update yargs to version 7.0.1 ([#349](https://github.com/showdownjs/showdown/issues/349)) ([9308d7b](https://github.com/showdownjs/showdown/commit/9308d7b))
* **package:** update yargs to version 8.0.1 ([#385](https://github.com/showdownjs/showdown/issues/385)) ([5fd847b](https://github.com/showdownjs/showdown/commit/5fd847b))
* **simpleAutoLinks:** URLs with emphasis/strikethrough are parsed ([5c50675](https://github.com/showdownjs/showdown/commit/5c50675)), closes [#347](https://github.com/showdownjs/showdown/issues/347)
* **tables:** pipe char can now be escaped ([1ebc195](https://github.com/showdownjs/showdown/commit/1ebc195)), closes [#345](https://github.com/showdownjs/showdown/issues/345)
* **url parsing:** fix url edge case parsing in images and links ([30aa18c](https://github.com/showdownjs/showdown/commit/30aa18c))
* **images:** add support for image's implicit reference syntax ([0c6c07b](https://github.com/showdownjs/showdown/commit/0c6c07b)), closes [#366](https://github.com/showdownjs/showdown/issues/366)
* **literalMidWordAsterisks:** add option for mid word asterisks ([5bec8f9](https://github.com/showdownjs/showdown/commit/5bec8f9))
* **openLinksInNewWindow:** add option to open all links in a new window ([50235d6](https://github.com/showdownjs/showdown/commit/50235d6)), closes [#362](https://github.com/showdownjs/showdown/issues/362) [#337](https://github.com/showdownjs/showdown/issues/337) [#249](https://github.com/showdownjs/showdown/issues/249) [#247](https://github.com/showdownjs/showdown/issues/247) [#222](https://github.com/showdownjs/showdown/issues/222)
* **encodeAmpsAndAngles:** fix > and <encoding([7f43b79](https://github.com/showdownjs/showdown/commit/7f43b79)),closes [#236](https://github.com/showdownjs/showdown/issues/236)
* **encodeEmail:** now produces valid emails ([605d8b7](https://github.com/showdownjs/showdown/commit/605d8b7)), closes [#340](https://github.com/showdownjs/showdown/issues/340)
* **flavor: github:** new version of github does not use prefix 'user-content' in headers ([368f0b6](https://github.com/showdownjs/showdown/commit/368f0b6))
* **codeSpans:** add - and = to escaped chars inside code spans ([4243a31](https://github.com/showdownjs/showdown/commit/4243a31))
* **italicsAndBold:** fix inconsistency in italicsAndBold parsing ([a4f05d4](https://github.com/showdownjs/showdown/commit/a4f05d4)), closes [#332](https://github.com/showdownjs/showdown/issues/332)
* **literalMidWordUnderscores:** fix inconsistent behavior of emphasis and strong with literalMidWordUndescores ([0292ae0](https://github.com/showdownjs/showdown/commit/0292ae0)), closes [#333](https://github.com/showdownjs/showdown/issues/333)
* **simplifiedAutoLink:** fix missing spaces before and after email addresses ([5190b6a](https://github.com/showdownjs/showdown/commit/5190b6a)), closes [#330](https://github.com/showdownjs/showdown/issues/330)
### Features
* **encodeEmail:** add option to enable/disable mail obfuscation ([90c52b8](https://github.com/showdownjs/showdown/commit/90c52b8))
### Notes
This release also improves performance a bit (around 8%)
* **ghCompatibleHeaderId:** improve the number of removed chars ([d499feb](https://github.com/showdownjs/showdown/commit/d499feb))
* **IE8:** fix for IE8 error on using isUndefined function ([561dc5f](https://github.com/showdownjs/showdown/commit/561dc5f)), closes [#280](https://github.com/showdownjs/showdown/issues/280)
* **options:** fix ghCompatibleHeaderId that was set as string instead of boolean ([de7c37e](https://github.com/showdownjs/showdown/commit/de7c37e))
* **simpleLineBreaks:** fix simpleLineBreaks option not working with non-ASCII chars and markdown delimiters ([b1c458a](https://github.com/showdownjs/showdown/commit/b1c458a)), closes [#318](https://github.com/showdownjs/showdown/issues/318) [#323](https://github.com/showdownjs/showdown/issues/323)
### Features
* **CLI:** add -q (quiet) and -m (mute) mode to CLI ([f3b86f0](https://github.com/showdownjs/showdown/commit/f3b86f0))
* **CLI:flavor:** add flavor option to CLI ([2d6cd1e](https://github.com/showdownjs/showdown/commit/2d6cd1e))
* **getFlavor:** add getFlavor method to showdown and Converter ([0eaf105](https://github.com/showdownjs/showdown/commit/0eaf105))
* **ghMentions:** add support for github's @mentions ([f2671c0](https://github.com/showdownjs/showdown/commit/f2671c0)), closes [#51](https://github.com/showdownjs/showdown/issues/51)
### BREAKING CHANGES:
* CLI tool now uses the same option defaults as showdown main library. This mean
the default flavor is vanilla and ghCodeBlocks options is enabled by default.
To update, add `--ghCodeBlocks="false"` to the command.
* parser slowness with certain inputs ([da8fb53](https://github.com/showdownjs/showdown/commit/da8fb53)), closes [#315](https://github.com/showdownjs/showdown/issues/315)
### Features
* **requireSpaceBeforeHeadingText:** option to make space between `#` and header text mandatory ([5d19877](https://github.com/showdownjs/showdown/commit/5d19877)), closes [#277](https://github.com/showdownjs/showdown/issues/277)
* **lists:** lines with multiple dashes being parsed as multilists ([10b3410](https://github.com/showdownjs/showdown/commit/10b3410)), closes [#312](https://github.com/showdownjs/showdown/issues/312)
* **simpleLineBreaks:** option that parses linebreaks as <br/>. This option enables linebreaks to always be treated as `<br />` tags
without needing to add spaces in front of the line, the same way GitHub does. ([0942b5e](https://github.com/showdownjs/showdown/commit/0942b5e)), closes [#206](https://github.com/showdownjs/showdown/issues/206)
* **excludeTrailingPunctuationFromURLs:** option that excludes trailing punctuation from auto linked URLs. ([d2fc2a0](https://github.com/showdownjs/showdown/commit/d2fc2a0)), closes [#266](https://github.com/showdownjs/showdown/issues/266) [#308](https://github.com/showdownjs/showdown/issues/308)
* **disableForced4SpacesIndentedSublists:** option that disables the requirement of indenting nested sublists by 4 spaces. The option is disabled by default ([0be39bc](https://github.com/showdownjs/showdown/commit/0be39bc))
* **bower:** fix sourceMappingURL errors in bower by including source ([9b5a233](https://github.com/showdownjs/showdown/commit/9b5a233)), closes [#200](https://github.com/showdownjs/showdown/issues/200)
* **comments:** Fix html comment parser ([238726c](https://github.com/showdownjs/showdown/commit/238726c)), closes [#276](https://github.com/showdownjs/showdown/issues/276)
* **tables:** add check for undefined on text due to failing to parse tables ([6e30a48](https://github.com/showdownjs/showdown/commit/6e30a48)), author [stewartmckee](https://github.com/stewartmckee), closes [#257](https://github.com/showdownjs/showdown/pull/247)
* **literalMidWordUnderscores:** fix different behavior with asterisks ([e86aea8](https://github.com/showdownjs/showdown/commit/e86aea8)), closes [#198](https://github.com/showdownjs/showdown/issues/198)
* **simpleautolink:** fix mail simpleAutoLink to ignore urls with @ symbol ([8ebb25e](https://github.com/showdownjs/showdown/commit/8ebb25e)), closes [#204](https://github.com/showdownjs/showdown/issues/204)
### Features
* **eventDispatcher:** add an event dispatcher to converter ([2734326](https://github.com/showdownjs/showdown/commit/2734326))
* **hashHTMLSpans:** add support for hashing span elements ([3097bd4](https://github.com/showdownjs/showdown/commit/3097bd4)), closes [#196](https://github.com/showdownjs/showdown/issues/196) [#175](https://github.com/showdownjs/showdown/issues/175)
* add support for md span elements in table headers ([789dc18](http://github.com/showdownjs/showdown/commit/789dc18)), closes [#179](http://github.com/showdownjs/showdown/issues/179)
* fix broken em/strong tags when used with literalMidWordUnderscores ([7ee2017](http://github.com/showdownjs/showdown/commit/7ee2017)), closes [#179](http://github.com/showdownjs/showdown/issues/179)
* fix underscores not being correctly parsed when used in conjunction with literalMidWordsUnderscores option ([c9e85f1](http://github.com/showdownjs/showdown/commit/c9e85f1))
* **codeSpans:** Fix issue with code html tags not being correctly escaped ([5f043ca](http://github.com/showdownjs/showdown/commit/5f043ca))
* **images:** fix alt attribute not being escaped correctly ([542194e](http://github.com/showdownjs/showdown/commit/542194e))
* **headerLevelStart:** fix for NaN error when specifying a non number as headerLevelStart param ([be72b487](http://github.com/showdownjs/showdown/commit/be72b487))
* **headerLevelStart:** add support for setting the header starting level ([b84ac67d](http://github.com/showdownjs/showdown/commit/b84ac67d), closes [#69](http://github.com/showdownjs/showdown/issues/69))
* **image dimensions:** add support for setting image dimensions within markdown syntax ([af82c2b6](http://github.com/showdownjs/showdown/commit/af82c2b6), closes [#143](http://github.com/showdownjs/showdown/issues/143))
* **noHeaderId:** add option to suppress automatic generation of ids in headers ([7ac893e9](http://github.com/showdownjs/showdown/commit/7ac893e9))
* **showdown.getDefaultOptions:** add method to retrieve default global options keypairs ([2de53a7d](http://github.com/showdownjs/showdown/commit/2de53a7d))
* Deprecates `showdown.extensions` property. To migrate, extensions should use the new method `showdown.extension(<ext name>, <extension>)` to register.
For more information on the new extension loading mechanism, please check the wiki pages.
- add unique id prefix and suffix to headers ([c367a4b9](http://github.com/showdownjs/showdown/commit/c367a4b9), closes [#81](http://github.com/showdownjs/showdown/issues/81), [#82](http://github.com/showdownjs/showdown/issues/82))
* **options.omitExtraWLInCodeBlocks:** fix for options.omitExtraWLInCodeBlocks only applying in gitHub flavoured code b ([e6f40e19](http://github.com/showdownjs/showdown/commit/e6f40e19))
* **showdown:** fix for options merging into globalOptions ([ddd6011d](http://github.com/showdownjs/showdown/commit/ddd6011d), closes [#153](http://github.com/showdownjs/showdown/issues/153))
The system, however, is not final and will probably be changed until the final version([0fd10cb] (http://github.com/showdownjs/showdown/commit/0fd10cb))
* **allowBlockIndents:** indented inline block elements can now be parsed as markdown ([f6326b84](http://github.com/showdownjs/showdown/commit/f6326b84))
* **omitExtraWLInCodeBlocks:** add option to omit extra newline at the end of codeblocks ([141e3f5](http://github.com/showdownjs/showdown/commit/141e3f5))
* **prefixHeaderId:** add options to prefix header ids to prevent id clash ([141e3f5](http://github.com/showdownjs/showdown/commit/141e3f5))
* **extensions:** showdown extensions were removed from core package and now live in their own repository. See the [project's github page](https://github.com/showdownjs) for available extensions
