diff --git a/.eslintrc.js b/.eslintrc.js
index 4658fb9792..3ba045803f 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -1,8 +1,11 @@
 module.exports = {
-    plugins: ["matrix-org"],
+    plugins: [
+        "matrix-org",
+    ],
     extends: [
         "plugin:matrix-org/babel",
         "plugin:matrix-org/react",
+        "plugin:matrix-org/a11y",
     ],
     env: {
         browser: true,
@@ -36,6 +39,26 @@ module.exports = {
                 "Use Media helper instead to centralise access for customisation.",
             ),
         ],
+
+        // There are too many a11y violations to fix at once
+        // Turn violated rules off until they are fixed
+        "jsx-a11y/alt-text": "off",
+        "jsx-a11y/anchor-is-valid": "off",
+        "jsx-a11y/aria-activedescendant-has-tabindex": "off",
+        "jsx-a11y/click-events-have-key-events": "off",
+        "jsx-a11y/iframe-has-title": "off",
+        "jsx-a11y/interactive-supports-focus": "off",
+        "jsx-a11y/label-has-associated-control": "off",
+        "jsx-a11y/media-has-caption": "off",
+        "jsx-a11y/mouse-events-have-key-events": "off",
+        "jsx-a11y/no-autofocus": "off",
+        "jsx-a11y/no-noninteractive-element-interactions": "off",
+        "jsx-a11y/no-noninteractive-element-to-interactive-role": "off",
+        "jsx-a11y/no-noninteractive-tabindex": "off",
+        "jsx-a11y/no-static-element-interactions": "off",
+        "jsx-a11y/role-has-required-aria-props": "off",
+        "jsx-a11y/role-supports-aria-props": "off",
+        "jsx-a11y/tabindex-no-positive": "off",
     },
     overrides: [{
         files: [
diff --git a/package.json b/package.json
index 9144478205..8831f25725 100644
--- a/package.json
+++ b/package.json
@@ -166,7 +166,8 @@
     "enzyme-to-json": "^3.6.2",
     "eslint": "7.18.0",
     "eslint-config-google": "^0.14.0",
-    "eslint-plugin-matrix-org": "github:matrix-org/eslint-plugin-matrix-org#48ec1e6af2cfb8310b9a6e23edf2dc7a26ddd580",
+    "eslint-plugin-jsx-a11y": "^6.5.1",
+    "eslint-plugin-matrix-org": "github:matrix-org/eslint-plugin-matrix-org#2fc59ae12ff551e91c41a1b185be25c77ad02190",
     "eslint-plugin-react": "^7.22.0",
     "eslint-plugin-react-hooks": "^4.2.0",
     "glob": "^7.1.6",
diff --git a/src/components/structures/ScrollPanel.tsx b/src/components/structures/ScrollPanel.tsx
index 3ebe93be04..e58a60b2aa 100644
--- a/src/components/structures/ScrollPanel.tsx
+++ b/src/components/structures/ScrollPanel.tsx
@@ -958,7 +958,7 @@ export default class ScrollPanel extends React.Component<IProps> {
             >
                 { this.props.fixedChildren }
                 <div className="mx_RoomView_messageListWrapper">
-                    <ol ref={this.itemlist} className="mx_RoomView_MessageList" aria-live="polite" role="list">
+                    <ol ref={this.itemlist} className="mx_RoomView_MessageList" aria-live="polite">
                         { this.props.children }
                     </ol>
                 </div>
diff --git a/src/components/views/context_menus/TagTileContextMenu.js b/src/components/views/context_menus/TagTileContextMenu.js
index d7b21756f6..71e1e614d2 100644
--- a/src/components/views/context_menus/TagTileContextMenu.js
+++ b/src/components/views/context_menus/TagTileContextMenu.js
@@ -88,7 +88,7 @@ export default class TagTileContextMenu extends React.Component {
         let createSpaceOption;
         if (GroupStore.isUserPrivileged(this.props.tag)) {
             createSpaceOption = <>
-                <hr className="mx_TagTileContextMenu_separator" role="separator" />
+                <hr className="mx_TagTileContextMenu_separator" />
                 <MenuItem className="mx_TagTileContextMenu_item mx_TagTileContextMenu_createSpace" onClick={this._onCreateSpaceClick}>
                     { _t("Create Space") }
                 </MenuItem>
@@ -99,10 +99,10 @@ export default class TagTileContextMenu extends React.Component {
             <MenuItem className="mx_TagTileContextMenu_item mx_TagTileContextMenu_viewCommunity" onClick={this._onViewCommunityClick}>
                 { _t('View Community') }
             </MenuItem>
-            { (moveUp || moveDown) ? <hr className="mx_TagTileContextMenu_separator" role="separator" /> : null }
+            { (moveUp || moveDown) ? <hr className="mx_TagTileContextMenu_separator" /> : null }
             { moveUp }
             { moveDown }
-            <hr className="mx_TagTileContextMenu_separator" role="separator" />
+            <hr className="mx_TagTileContextMenu_separator" />
             <MenuItem className="mx_TagTileContextMenu_item mx_TagTileContextMenu_hideCommunity" onClick={this._onRemoveClick}>
                 { _t("Unpin") }
             </MenuItem>
diff --git a/src/components/views/messages/MFileBody.tsx b/src/components/views/messages/MFileBody.tsx
index 891a48d8b0..6cffaa8675 100644
--- a/src/components/views/messages/MFileBody.tsx
+++ b/src/components/views/messages/MFileBody.tsx
@@ -252,12 +252,13 @@ export default class MFileBody extends React.Component<IProps, IState> {
                 <span className="mx_MFileBody">
                     { placeholder }
                     { showDownloadLink && <div className="mx_MFileBody_download">
-                        <div style={{ display: "none" }}>
+                        <div aria-hidden style={{ display: "none" }}>
                             { /*
                               * Add dummy copy of the "a" tag
                               * We'll use it to learn how the download link
                               * would have been styled if it was rendered inline.
                               */ }
+                            { /* eslint-disable-next-line jsx-a11y/anchor-has-content */ }
                             <a ref={this.dummyLink} />
                         </div>
                         { /*
diff --git a/src/components/views/messages/ViewSourceEvent.tsx b/src/components/views/messages/ViewSourceEvent.tsx
index e1de5137d9..3e6d47dc13 100644
--- a/src/components/views/messages/ViewSourceEvent.tsx
+++ b/src/components/views/messages/ViewSourceEvent.tsx
@@ -20,6 +20,7 @@ import classNames from 'classnames';
 
 import { replaceableComponent } from "../../../utils/replaceableComponent";
 import { MatrixClientPeg } from "../../../MatrixClientPeg";
+import { _t } from '../../../languageHandler';
 
 interface IProps {
     mxEvent: MatrixEvent;
@@ -75,9 +76,9 @@ export default class ViewSourceEvent extends React.PureComponent<IProps, IState>
 
         return <span className={classes}>
             { content }
-            <a
+            <button
+                title={_t('toggle event')}
                 className="mx_ViewSourceEvent_toggle"
-                href="#"
                 onClick={this.onToggle}
             />
         </span>;
diff --git a/src/i18n/strings/en_EN.json b/src/i18n/strings/en_EN.json
index b3f7b66d39..93cb7e3a8b 100644
--- a/src/i18n/strings/en_EN.json
+++ b/src/i18n/strings/en_EN.json
@@ -2120,6 +2120,7 @@
     "edited": "edited",
     "Submit logs": "Submit logs",
     "Can't load this message": "Can't load this message",
+    "toggle event": "toggle event",
     "Share location": "Share location",
     "Share custom location": "Share custom location",
     "Share my current location as a once off": "Share my current location as a once off",
diff --git a/yarn.lock b/yarn.lock
index a6a4cf9127..00acd506ce 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1038,6 +1038,14 @@
     pirates "^4.0.0"
     source-map-support "^0.5.16"
 
+"@babel/runtime-corejs3@^7.10.2":
+  version "7.16.7"
+  resolved "https://registry.yarnpkg.com/@babel/runtime-corejs3/-/runtime-corejs3-7.16.7.tgz#a762745fe8b4d61a26444a9151e6586d36044dde"
+  integrity sha512-MiYR1yk8+TW/CpOD0CyX7ve9ffWTKqLk/L6pk8TPl0R8pNi+1pFY8fH9yET55KlvukQ4PAWfXsGr2YHVjcI4Pw==
+  dependencies:
+    core-js-pure "^3.19.0"
+    regenerator-runtime "^0.13.4"
+
 "@babel/runtime@^7.0.0", "@babel/runtime@^7.12.13", "@babel/runtime@^7.12.5", "@babel/runtime@^7.15.4", "@babel/runtime@^7.5.5", "@babel/runtime@^7.8.4", "@babel/runtime@^7.8.7", "@babel/runtime@^7.9.2":
   version "7.16.3"
   resolved "https://registry.yarnpkg.com/@babel/runtime/-/runtime-7.16.3.tgz#b86f0db02a04187a3c17caa77de69840165d42d5"
@@ -1045,6 +1053,13 @@
   dependencies:
     regenerator-runtime "^0.13.4"
 
+"@babel/runtime@^7.10.2", "@babel/runtime@^7.16.3":
+  version "7.16.7"
+  resolved "https://registry.yarnpkg.com/@babel/runtime/-/runtime-7.16.7.tgz#03ff99f64106588c9c403c6ecb8c3bafbbdff1fa"
+  integrity sha512-9E9FJowqAsytyOY6LG+1KuueckRL+aQW+mKvXRXnuFGyRAyepJPmEo9vgMfXUA6O9u3IeEdv9MAkppFcaQwogQ==
+  dependencies:
+    regenerator-runtime "^0.13.4"
+
 "@babel/template@^7.16.0", "@babel/template@^7.3.3":
   version "7.16.0"
   resolved "https://registry.yarnpkg.com/@babel/template/-/template-7.16.0.tgz#d16a35ebf4cd74e202083356fab21dd89363ddd6"
@@ -2200,6 +2215,14 @@ argparse@^2.0.1:
   resolved "https://registry.yarnpkg.com/argparse/-/argparse-2.0.1.tgz#246f50f3ca78a3240f6c997e8a9bd1eac49e4b38"
   integrity sha512-8+9WqebbFzpX9OR+Wa6O29asIogeRMzcGtAINdpMHHyAg10f05aSFVBbcEqGf/PXw1EjAZ+q2/bEBg3DvurK3Q==
 
+aria-query@^4.2.2:
+  version "4.2.2"
+  resolved "https://registry.yarnpkg.com/aria-query/-/aria-query-4.2.2.tgz#0d2ca6c9aceb56b8977e9fed6aed7e15bbd2f83b"
+  integrity sha512-o/HelwhuKpTj/frsOsbNLNgnNGVIFsVP/SW2BSF14gVl7kAfMOJ6/8wUAUvG1R1NHKrfG+2sHZTu0yauT1qBrA==
+  dependencies:
+    "@babel/runtime" "^7.10.2"
+    "@babel/runtime-corejs3" "^7.10.2"
+
 arr-diff@^4.0.0:
   version "4.0.0"
   resolved "https://registry.yarnpkg.com/arr-diff/-/arr-diff-4.0.0.tgz#d6461074febfec71e7e15235761a329a5dc7c520"
@@ -2299,6 +2322,11 @@ assign-symbols@^1.0.0:
   resolved "https://registry.yarnpkg.com/assign-symbols/-/assign-symbols-1.0.0.tgz#59667f41fadd4f20ccbc2bb96b8d4f7f78ec0367"
   integrity sha1-WWZ/QfrdTyDMvCu5a41Pf3jsA2c=
 
+ast-types-flow@^0.0.7:
+  version "0.0.7"
+  resolved "https://registry.yarnpkg.com/ast-types-flow/-/ast-types-flow-0.0.7.tgz#f70b735c6bca1a5c9c22d982c3e39e7feba3bdad"
+  integrity sha1-9wtzXGvKGlycItmCw+Oef+ujva0=
+
 astral-regex@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/astral-regex/-/astral-regex-2.0.0.tgz#483143c567aeed4785759c0865786dc77d7d2e31"
@@ -2347,6 +2375,16 @@ aws4@^1.8.0:
   resolved "https://registry.yarnpkg.com/aws4/-/aws4-1.11.0.tgz#d61f46d83b2519250e2784daf5b09479a8b41c59"
   integrity sha512-xh1Rl34h6Fi1DC2WWKfxUTVqRsNnr6LsKz2+hfwDxQJWmrx8+c7ylaqBMcHfl1U1r2dsifOvKX3LQuLNZ+XSvA==
 
+axe-core@^4.3.5:
+  version "4.3.5"
+  resolved "https://registry.yarnpkg.com/axe-core/-/axe-core-4.3.5.tgz#78d6911ba317a8262bfee292aeafcc1e04b49cc5"
+  integrity sha512-WKTW1+xAzhMS5dJsxWkliixlO/PqC4VhmO9T4juNYcaTg9jzWiJsou6m5pxWYGfigWbwzJWeFY6z47a+4neRXA==
+
+axobject-query@^2.2.0:
+  version "2.2.0"
+  resolved "https://registry.yarnpkg.com/axobject-query/-/axobject-query-2.2.0.tgz#943d47e10c0b704aa42275e20edf3722648989be"
+  integrity sha512-Td525n+iPOOyUQIeBfcASuG6uJsDOITl7Mds5gFyerkWiX7qhUTdYUBlSgNMyVqtSJqwpt1kXGLdUt6SykLMRA==
+
 babel-jest@^26.6.3:
   version "26.6.3"
   resolved "https://registry.yarnpkg.com/babel-jest/-/babel-jest-26.6.3.tgz#d87d25cb0037577a0c89f82e5755c5d293c01056"
@@ -2969,6 +3007,11 @@ core-js-compat@^3.18.0, core-js-compat@^3.19.1:
     browserslist "^4.18.1"
     semver "7.0.0"
 
+core-js-pure@^3.19.0:
+  version "3.20.2"
+  resolved "https://registry.yarnpkg.com/core-js-pure/-/core-js-pure-3.20.2.tgz#5d263565f0e34ceeeccdc4422fae3e84ca6b8c0f"
+  integrity sha512-CmWHvSKn2vNL6p6StNp1EmMIfVY/pqn3JLAjfZQ8WZGPOlGoO92EkX9/Mk81i6GxvoPXjUqEQnpM3rJ5QxxIOg==
+
 core-js@^1.0.0:
   version "1.2.7"
   resolved "https://registry.yarnpkg.com/core-js/-/core-js-1.2.7.tgz#652294c14651db28fa93bd2d5ff2983a4f08c636"
@@ -3106,6 +3149,11 @@ d@1, d@^1.0.1:
     es5-ext "^0.10.50"
     type "^1.0.1"
 
+damerau-levenshtein@^1.0.7:
+  version "1.0.7"
+  resolved "https://registry.yarnpkg.com/damerau-levenshtein/-/damerau-levenshtein-1.0.7.tgz#64368003512a1a6992593741a09a9d31a836f55d"
+  integrity sha512-VvdQIPGdWP0SqFXghj79Wf/5LArmreyMsGLa6FG6iC4t3j7j5s71TrwWmT/4akbDQIqjfACkLZmjXhA7g2oUZw==
+
 dashdash@^1.12.0:
   version "1.14.1"
   resolved "https://registry.yarnpkg.com/dashdash/-/dashdash-1.14.1.tgz#853cfa0f7cbe2fed5de20326b8dd581035f6e2f0"
@@ -3387,6 +3435,11 @@ emoji-regex@^8.0.0:
   resolved "https://registry.yarnpkg.com/emoji-regex/-/emoji-regex-8.0.0.tgz#e818fd69ce5ccfcb404594f842963bf53164cc37"
   integrity sha512-MSjYzcWNOA0ewAHpz0MxpYFvwg6yjy1NG3xteoqz644VCo/RPgnr1/GGt+ic3iJTzQ8Eu3TdM14SawnVUmGE6A==
 
+emoji-regex@^9.2.2:
+  version "9.2.2"
+  resolved "https://registry.yarnpkg.com/emoji-regex/-/emoji-regex-9.2.2.tgz#840c8803b0d8047f4ff0cf963176b32d4ef3ed72"
+  integrity sha512-L18DaJsXSUk2+42pv8mLs5jJT2hqFkFE4j21wOmgbUqsZ2hL72NsUU785g9RXgo3s0ZNgVl42TiHp3ZtOv/Vyg==
+
 emojibase-data@^6.2.0:
   version "6.2.0"
   resolved "https://registry.yarnpkg.com/emojibase-data/-/emojibase-data-6.2.0.tgz#db6c75c36905284fa623f4aa5f468d2be6ed364a"
@@ -3658,9 +3711,27 @@ eslint-plugin-import@^2.25.2:
     resolve "^1.20.0"
     tsconfig-paths "^3.11.0"
 
-"eslint-plugin-matrix-org@github:matrix-org/eslint-plugin-matrix-org#48ec1e6af2cfb8310b9a6e23edf2dc7a26ddd580":
+eslint-plugin-jsx-a11y@^6.5.1:
+  version "6.5.1"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-jsx-a11y/-/eslint-plugin-jsx-a11y-6.5.1.tgz#cdbf2df901040ca140b6ec14715c988889c2a6d8"
+  integrity sha512-sVCFKX9fllURnXT2JwLN5Qgo24Ug5NF6dxhkmxsMEUZhXRcGg+X3e1JbJ84YePQKBl5E0ZjAH5Q4rkdcGY99+g==
+  dependencies:
+    "@babel/runtime" "^7.16.3"
+    aria-query "^4.2.2"
+    array-includes "^3.1.4"
+    ast-types-flow "^0.0.7"
+    axe-core "^4.3.5"
+    axobject-query "^2.2.0"
+    damerau-levenshtein "^1.0.7"
+    emoji-regex "^9.2.2"
+    has "^1.0.3"
+    jsx-ast-utils "^3.2.1"
+    language-tags "^1.0.5"
+    minimatch "^3.0.4"
+
+"eslint-plugin-matrix-org@github:matrix-org/eslint-plugin-matrix-org#2fc59ae12ff551e91c41a1b185be25c77ad02190":
   version "0.3.5"
-  resolved "https://codeload.github.com/matrix-org/eslint-plugin-matrix-org/tar.gz/48ec1e6af2cfb8310b9a6e23edf2dc7a26ddd580"
+  resolved "https://codeload.github.com/matrix-org/eslint-plugin-matrix-org/tar.gz/2fc59ae12ff551e91c41a1b185be25c77ad02190"
 
 eslint-plugin-react-hooks@^4.2.0:
   version "4.3.0"
@@ -5770,7 +5841,7 @@ jsprim@^1.2.2:
     json-schema "0.4.0"
     verror "1.10.0"
 
-"jsx-ast-utils@^2.4.1 || ^3.0.0":
+"jsx-ast-utils@^2.4.1 || ^3.0.0", jsx-ast-utils@^3.2.1:
   version "3.2.1"
   resolved "https://registry.yarnpkg.com/jsx-ast-utils/-/jsx-ast-utils-3.2.1.tgz#720b97bfe7d901b927d87c3773637ae8ea48781b"
   integrity sha512-uP5vu8xfy2F9A6LGC22KO7e2/vGTS1MhP+18f++ZNlf0Ohaxbc9nIEwHAsejlJKyzfZzU5UIhe5ItYkitcZnZA==
@@ -5834,6 +5905,18 @@ known-css-properties@^0.21.0:
   resolved "https://registry.yarnpkg.com/known-css-properties/-/known-css-properties-0.21.0.tgz#15fbd0bbb83447f3ce09d8af247ed47c68ede80d"
   integrity sha512-sZLUnTqimCkvkgRS+kbPlYW5o8q5w1cu+uIisKpEWkj31I8mx8kNG162DwRav8Zirkva6N5uoFsm9kzK4mUXjw==
 
+language-subtag-registry@~0.3.2:
+  version "0.3.21"
+  resolved "https://registry.yarnpkg.com/language-subtag-registry/-/language-subtag-registry-0.3.21.tgz#04ac218bea46f04cb039084602c6da9e788dd45a"
+  integrity sha512-L0IqwlIXjilBVVYKFT37X9Ih11Um5NEl9cbJIuU/SwP/zEEAbBPOnEeeuxVMf45ydWQRDQN3Nqc96OgbH1K+Pg==
+
+language-tags@^1.0.5:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/language-tags/-/language-tags-1.0.5.tgz#d321dbc4da30ba8bf3024e040fa5c14661f9193a"
+  integrity sha1-0yHbxNowuovzAk4ED6XBRmH5GTo=
+  dependencies:
+    language-subtag-registry "~0.3.2"
+
 leven@^3.1.0:
   version "3.1.0"
   resolved "https://registry.yarnpkg.com/leven/-/leven-3.1.0.tgz#77891de834064cccba82ae7842bb6b14a13ed7f2"