diff --git a/RELEASE_CHECKLIST.md b/RELEASE_CHECKLIST.md
index 02ba16e7f4..9bf9726090 100644
--- a/RELEASE_CHECKLIST.md
+++ b/RELEASE_CHECKLIST.md
@@ -22,5 +22,7 @@
  - [ ] Create a signed tag locally and push it up. Tag should be named `xx.yy.zz`.
  - [ ] Go to Github and add release notes from the relevant `CHANGELOG` section.
  - [ ] Bump constraints in league/commonmark-extras (and other official extensions) and tag a new release of them
+ - [ ] Resync project on <https://libraries.io/packagist/league%2Fcommonmark/>
+ - [ ] Update release notes and supported branches on Tidelift
  - [ ] ???
  - [ ] PROFIT!!
diff --git a/docs/1.0/basic-usage.md b/docs/1.0/basic-usage.md
index ce1ba742b4..170bb699f5 100644
--- a/docs/1.0/basic-usage.md
+++ b/docs/1.0/basic-usage.md
@@ -24,13 +24,13 @@ echo $converter->convertToHtml('# Hello World!');
 <i class="fa fa-exclamation-triangle"></i>
 **Important:** See the [security](/1.0/security/) section for important details on avoiding security misconfigurations.
 
-The actual conversion process requires three steps:
+The actual conversion process has three steps:
 
- 1. Create an `Environment`, adding whichever extensions/parser/renders you need
+ 1. Creating an `Environment`, adding whichever extensions/parser/renders you need
  2. Parsing the Markdown input into an AST
  3. Rendering the AST document as HTML
 
-You can do this yourself if you wish:
+`CommonMarkConverter` handles this for you, but you can execute that process yourself if you wish:
 
 ~~~php
 <?php
@@ -53,4 +53,6 @@ echo $htmlRenderer->renderBlock($document);
 
 [Additional customization](/1.0/customization/overview/) is also possible.
 
+## Supported Character Encodings
+
 Please note that only UTF-8 and ASCII encodings are supported.  If your Markdown uses a different encoding please convert it to UTF-8 before running it through this library.
diff --git a/docs/1.0/customization/block-parsing.md b/docs/1.0/customization/block-parsing.md
index e60212a371..1d5f6c7742 100644
--- a/docs/1.0/customization/block-parsing.md
+++ b/docs/1.0/customization/block-parsing.md
@@ -12,7 +12,13 @@ Block parsers should implement `BlockParserInterface` and implement the followin
 
 ## parse()
 
-When parsing a new line, the `DocParser` iterates through all registered block parsers and calls their `parse()` method.  Each parser must determine whether it can handle the given line; if so, it should parse the given block and return true.
+~~~php
+<?php
+
+public function parse(ContextInterface $context, Cursor $cursor): bool;
+~~~
+
+When parsing a new line, the `DocParser` iterates through all registered block parsers and calls their `parse()` method.  Each parser must determine whether it can handle the given line; if so, it should parse the given block and return `true`.
 
 ### Parameters
 
@@ -31,6 +37,7 @@ Returning `true` tells the engine that you've successfully parsed the block at t
 ## Tips
 
 * For best performance, `return false` as soon as possible
+* Your `parse()` method may be called thousands of times so be sure your code is optimized
 
 ## Block Elements
 
@@ -43,7 +50,7 @@ Block elements also play a role during the parsing process as they tell the unde
 | Method                    | Purpose                                                                                               |
 | ------------------------- | ----------------------------------------------------------------------------------------------------- |
 | `canContain(...)`         | Tell the engine whether a subsequent block can be added as a child of yours                           |
-| `isCode()`                | Returns whether this block represents `<code>`                                                        |
+| `isCode()`                | Returns whether this block represents an extra-greedy `<code>` block                                  |
 | `matchesNextLine(...)`    | Returns whether this block continues onto the next line (some blocks are multi-line)                  |
 | `shouldLastLineBeBlank()` | Returns whether the last line should be blank (primarily used by `ListItem` elements)                 |
 | `finalize(...)`           | Finalizes the block after all child items have been added, thus marking it as closed for modification |
diff --git a/docs/1.0/customization/block-rendering.md b/docs/1.0/customization/block-rendering.md
index 49eb7f9176..9b32acd20f 100644
--- a/docs/1.0/customization/block-rendering.md
+++ b/docs/1.0/customization/block-rendering.md
@@ -14,6 +14,12 @@ All block renderers should implement `BlockRendererInterface` and its `render()`
 
 ## render()
 
+~~~php
+<?php
+
+public function render(AbstractBlock $block, ElementRendererInterface $htmlRenderer, bool $inTightList = false);
+~~~
+
 The `HtmlRenderer` will call this method whenever a supported block element is encountered in the AST being rendered.
 
 If the method can only handle certain block types, be sure to verify that you've been passed the correct type.
@@ -28,11 +34,24 @@ If the method can only handle certain block types, be sure to verify that you've
 
 The method must return the final HTML representation of the block and any of its contents. This can be an `HtmlElement` object (preferred; castable to a string), a string of raw HTML, or `null` if it could not render (and perhaps another renderer should give it a try).
 
-You are responsible for handling any escaping that may be necessary.
+If you choose to return an HTML `string` you are responsible for handling any escaping that may be necessary.
+
+#### `HtmlElement`
+
+Instead of manually building the HTML output yourself, you can leverage the `HtmlElement` to generate that for you.  For example:
+
+~~~php
+<?php
+
+use League\CommonMark\HtmlElement;
+
+$link = new HtmlElement('a', ['href' => 'https://github.com'], 'GitHub');
+$img = new HtmlElement('img', ['src' => 'logo.jpg'], '', true);
+~~~
 
 ## Designating Block Renderers
 
-When registering your render, you must tell the `Environment` which block element class your renderer should handle. For example:
+When registering your renderer, you must tell the `Environment` which block element class your renderer should handle. For example:
 
 ~~~php
 <?php
diff --git a/docs/1.0/customization/cursor.md b/docs/1.0/customization/cursor.md
index 77cad642e6..49f91d1ade 100644
--- a/docs/1.0/customization/cursor.md
+++ b/docs/1.0/customization/cursor.md
@@ -8,7 +8,7 @@ redirect_from: /0.20/customization/cursor/
 Cursor
 ======
 
-At it's core, a `Cursor` is just a fancy string that remembers your current position as you parse it  It contains a set of highly-optimized methods making it easy to parse characters, match regular expressions, and more.  
+A `Cursor` is essentially a fancy string wrapper that remembers your current position as you parse it.  It contains a set of highly-optimized methods making it easy to parse characters, match regular expressions, and more.
 
 ## Supported Encodings
 
@@ -16,7 +16,7 @@ As of now, only UTF-8 (and, by extension, ASCII) encoding is supported.
 
 ## Usage
 
-Instantiating a new `Cursor` is as simple as this:
+Instantiating a new `Cursor` is as simple as:
 
 ```php
 use League\CommonMark\Cursor;
@@ -24,7 +24,7 @@ use League\CommonMark\Cursor;
 $cursor = new Cursor('Hello World!');
 ```
 
-Or, if you're creating a custom [block parser](/1.0/customization/block-parsing/) or [inline renderer](/0.20/customization/inline-parsing/), a pre-configured `Cursor` will be provided to you with (with the `Cursor` already set to the current `position` trying to be parsed).
+Or, if you're creating a custom [block parser](/1.0/customization/block-parsing/) or [inline parser](/1.0/customization/inline-parsing/), a pre-configured `Cursor` will be provided to you with (with the `Cursor` already set to the current `position` trying to be parsed).
 
 ## Methods
 
@@ -42,6 +42,7 @@ You can then call any of the following methods to parse the string within that `
 | `peek(int $offset)`                | Returns the character `$offset` chars away without changing the current `position` of the cursor                                |
 | `getNextNonSpacePosition()`        | Returns the position of the next character which is not a space or tab                                                          |
 | `getNextNonSpaceCharacter()`       | Returns the next character which isn't a space (or tab)                                                                         |
+| `advance()`                        | Moves the cursor forward by 1 character                                                                                         |
 | `advanceBy(int $characters)`       | Moves the cursor forward by `$characters` characters                                                                            |
 | `advanceBy(int $characters, true)` | Moves the cursor forward by `$characters` characters, handling tabs as columns                                                  |
 | `advanceBySpaceOrTab()`            | Advances forward one character (and returns `true`) if it's a space or tab; returns false otherwise                             |
diff --git a/docs/1.0/customization/environment.md b/docs/1.0/customization/environment.md
index 61af963dcc..5eed8cb4c0 100644
--- a/docs/1.0/customization/environment.md
+++ b/docs/1.0/customization/environment.md
@@ -8,7 +8,7 @@ redirect_from: /0.20/customization/environment/
 The Environment
 ===============
 
-All parsers, renderers, etc. must be registered with the `Environment` class so that the library is aware of them.
+The `Environment` contains all of the parsers, renderers, configurations, etc. that the library uses during the conversion process.  You therefore must register all parsers, renderers, etc. with the `Environment` so that the library is aware of them.
 
 A pre-configured `Environment` can be obtained like this:
 
@@ -20,10 +20,39 @@ use League\CommonMark;
 $environment = Environment::createCommonMarkEnvironment();
 ~~~
 
-All of the core renders, parsers, etc. will be pre-registered and ready to go.
+All of the core renders, parsers, etc. needed to implement the CommonMark spec will be pre-registered and ready to go.
 
 You can customize this default `Environment` (or even a new, empty one) using any of the methods below (from the `ConfigurableEnvironmentInterface` interface).
-(These are the same methods used by `Environment::createCommonMarkEnvironment()` to register the standard functionality.)
+
+## mergeConfig()
+
+~~~php
+<?php
+
+public function mergeConfig(array $config = []);
+~~~
+
+Merges the given [configuration](/1.0/configuration/) settings into any existing ones.
+
+## setConfig()
+
+~~~php
+<?php
+
+public function setConfig(array $config = []);
+~~~
+
+Completely replaces the previous [configuration](/1.0/configuration/) settings with the new `$config` you provide.
+
+## addExtension()
+
+~~~php
+<?php
+
+public function addExtension(ExtensionInterface $extension);
+~~~
+
+Registers the given [extension](/1.0/customization/extensions/) with the environment.  This is typically how you'd integrate third-party extensions with this library.
 
 ## addBlockParser()
 
@@ -61,41 +90,43 @@ Registers the given `InlineParserInterface` with the environment with the given
 
 See [Inline Parsing](/1.0/customization/inline-parsing/) for details.
 
-## addInlineProcessor()
+## addInlineRenderer()
 
 ~~~php
 <?php
 
-public function addInlineProcessor(InlineProcessorInterface $processor);
+public function addInlineRenderer(string $inlineClass, InlineRendererInterface $renderer, int $priority = 0);
 ~~~
 
-Registers the given `InlineProcessorInterface` with the environment.
+Registers an `InlineRendererInterface` to handle a specific type of inline (`$inlineClass`) with the given priority (a higher number will be executed earlier).
+A single renderer can handle multiple inline classes, but you must register it separately for each type. (The same renderer instance can be re-used if desired.)
 
-**TODO:** Add documentation for this.
+See [Inline Rendering](/1.0/customization/inline-rendering/) for details.
 
-## addInlineRenderer()
+## addDelimiterProcessor()
 
 ~~~php
 <?php
 
-public function addInlineRenderer(string $inlineClass, InlineRendererInterface $renderer, int $priority = 0);
+public function addDelimiterProcessor(DelimiterProcessorInterface $processor);
 ~~~
 
-Registers an `InlineRendererInterface` to handle a specific type of inline (`$inlineClass`) with the given priority (a higher number will be executed earlier).
-A single renderer can handle multiple inline classes, but you must register it separately for each type. (The same renderer instance can be re-used if desired.)
+Registers the given `DelimiterProcessorInterface` with the environment.
 
-See [Inline Rendering](/1.0/customization/inline-rendering/) for details.
+See [Inline Parsing](/1.0/customization/delimiter-processing/) for details.
 
-## addDocumentProcessor()
+## addEventListener()
 
 ~~~php
 <?php
 
-public function addDocumentProcessor(DocumentProcessorInterface $processor, int $priority = 0);
+public function addEventListener(string $eventClass, callable $listener, int $priority = 0);
 ~~~
 
-Adds a new Document Processor which will [manipulate the AST](/1.0/customization/abstract-syntax-tree/) after parsing the document but before rendering it.
+Registers the given event listener with the environment.
+
+See [Event Dispatcher](/1.0/customization/event-dispatcher/) for details.
 
 ## Priority
 
-Each of these methods allows you to specify a numeric `$priority`.  In cases where multiple things are registered, the internal engine will attempt to use the higher-priority ones first, falling back to lower priority ones if the first one(s) were unable to handle things.
+Several of these methods allows you to specify a numeric `$priority`.  In cases where multiple things are registered, the internal engine will attempt to use the higher-priority ones first, falling back to lower priority ones if the first one(s) were unable to handle things.
diff --git a/docs/1.0/customization/event-dispatcher.md b/docs/1.0/customization/event-dispatcher.md
index 4fb24fd3e9..45d9a483a4 100644
--- a/docs/1.0/customization/event-dispatcher.md
+++ b/docs/1.0/customization/event-dispatcher.md
@@ -35,7 +35,7 @@ public function addEventListener(string $eventClass, callable $listener, int $pr
 The parameters for this method are:
 
 1. The fully-qualified name of the event class you wish to observe
-2. Any PHP callable to execute when that type of event is dispatched
+2. Any [PHP callable](https://www.php.net/manual/en/language.types.callable.php) to execute when that type of event is dispatched
 3. An optional priority (defaults to `0`)
 
 For example:
@@ -70,7 +70,7 @@ Listeners may call any method on the event to get more information about the eve
 
 This library supports the following default events which you can register listeners for:
 
-### `DocumentParsedEvent`
+### `League\CommonMark\Event\DocumentParsedEvent`
 
 This event is dispatched once all other processing is done.  This offers extensions the opportunity to inspect and modify the [Abstract Syntax Tree](/1.0/customization/abstract-syntax-tree/) prior to rendering.
 
diff --git a/docs/1.0/customization/extensions.md b/docs/1.0/customization/extensions.md
index 70e6b31a66..31afae6756 100644
--- a/docs/1.0/customization/extensions.md
+++ b/docs/1.0/customization/extensions.md
@@ -8,7 +8,7 @@ redirect_from: /0.20/customization/extensions/
 Extensions
 ==========
 
-Extensions provide a way to group multiple related parsers, processors, and/or renderers together with pre-defined priorities.  They are perfect for distributing your customizations as reusable, open-source packages that others can plug into their own projects!
+Extensions provide a way to group related parsers, renderers, etc. together with pre-defined priorities, configuration settings, etc.  They are perfect for distributing your customizations as reusable, open-source packages that others can plug into their own projects!
 
 To create an extension, simply create a new class implementing `ExtensionInterface`.  This has a single method where you're given a `ConfigurableEnvironmentInterface` to register whatever things you need to. For example:
 
@@ -19,7 +19,6 @@ final class EmojiExtension implements ExtensionInterface
     {
         $environment
             ->addInlineParser(new EmojiParser(), 20)
-            ->addDocumentProcessor(new ReplaceUnicodeEmojiProcessor(), 0)
             ->addInlineRenderer(Emoji::class, new EmojiRenderer(), 0)
         ;
     }
diff --git a/docs/1.0/customization/overview.md b/docs/1.0/customization/overview.md
index 17b2ed9473..59e1235c4a 100644
--- a/docs/1.0/customization/overview.md
+++ b/docs/1.0/customization/overview.md
@@ -34,6 +34,10 @@ otherwise you abort and the engine will try other parsers.  If no parser succeed
 
 Simple delimiter-based inlines (like emphasis, strikethrough, etc.) can be parsed without needing a dedicated inline parser by leveraging the new [Delimiter Processing](/1.0/customization/delimiter-processing/) functionality.
 
+## AST manipulation
+
+Once the [Abstract Syntax Tree](/1.0/customization/abstract-syntax-tree/) is parsed, you are free to access/manipulate it as needed before it's passed into the rendering engine.
+
 ## Customize HTML Output with Custom Renderers
 
 Renders convert the parsed blocks/inlines from the AST representation into HTML.  There are two types of renderers:
@@ -44,10 +48,6 @@ Renders convert the parsed blocks/inlines from the AST representation into HTML.
 When registering these with the environment, you must tell it which block/inline classes it should handle.  This allows you
 to essentially "swap out" built-in renderers with your own.
 
-## AST manipulation
-
-Once the [Abstract Syntax Tree](/1.0/customization/abstract-syntax-tree/) is parsed, you are free to access/manipulate it as needed before it's passed into the rendering engine.
-
 ## Examples
 
 Some examples of what's possible:
diff --git a/docs/1.0/security.md b/docs/1.0/security.md
index eb70952a4e..13b0fee708 100644
--- a/docs/1.0/security.md
+++ b/docs/1.0/security.md
@@ -8,6 +8,14 @@ redirect_from: /0.20/security/
 Security
 ========
 
+In order to be fully compliant with the CommonMark spec, certain security settings are disabled by default.  You will want to configure these settings if untrusted users will be providing the Markdown content:
+
+ - `html_input`: How to handle raw HTML
+ - `allow_unsafe_links`: Whether unsafe links are permitted
+ - `max_nesting_level`: Protected against long render times or segfaults
+
+Further information about each option can be found below.
+
 ## HTML Input
 
 **All HTML input is unescaped by default.**  This behavior ensures that league/commonmark is 100% compliant with the CommonMark spec.