diff --git a/.eslintignore b/.eslintignore
index f18c60d5..911c8af1 100644
--- a/.eslintignore
+++ b/.eslintignore
@@ -1,3 +1,4 @@
 dist
 test/lib/
 test/typescript/definitions.js
+docs
diff --git a/.eslintrc.js b/.eslintrc.js
index a0b5d7bf..ce6cad06 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -328,6 +328,7 @@ module.exports = {
     // eslint-plugin-import rules:
     "import/extensions": "never",
     "import/no-extraneous-dependencies": ["error", {"devDependencies": true, "optionalDependencies": false, "peerDependencies": false}],
+    "import/no-unassigned-import": "error",
 
     // Custom silencers:
     "camelcase": 0,
diff --git a/.github/workflows/node.js.yml b/.github/workflows/node.js.yml
index 40f4f7c9..b099dbcc 100644
--- a/.github/workflows/node.js.yml
+++ b/.github/workflows/node.js.yml
@@ -17,7 +17,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [10.x, 12.x, 14.x, 15.x]
+        node-version: [12.x, 14.x, 15.x]
         # See supported Node.js release schedule at https://nodejs.org/en/about/releases/
 
     steps:
diff --git a/package-lock.json b/package-lock.json
index fcf09406..ca41012b 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -4897,12 +4897,6 @@
         }
       }
     },
-    "text-encoding-utf-8": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/text-encoding-utf-8/-/text-encoding-utf-8-1.0.2.tgz",
-      "integrity": "sha512-8bw4MY9WjdsD2aMtO0OzOCY3pXGYNx2d2FfHRVUKkiCPDWjKuOlhLVASS+pD7VkLTVjW268LYJHwsnPFlBpbAg==",
-      "dev": true
-    },
     "text-table": {
       "version": "0.2.0",
       "resolved": "https://registry.npmjs.org/text-table/-/text-table-0.2.0.tgz",
diff --git a/package.json b/package.json
index cf2bf47b..b33b0aec 100644
--- a/package.json
+++ b/package.json
@@ -84,7 +84,6 @@
     "rollup-plugin-terser": "^5.3.0",
     "seek-bzip": "github:openpgpjs/seek-bzip#4b89457f20c0e1921b4689106a31c99782c29829",
     "sinon": "^4.3.0",
-    "text-encoding-utf-8": "^1.0.2",
     "tweetnacl": "github:openpgpjs/tweetnacl-js#3dae25bd3eaa77173f3405676b595721dde92eec",
     "typescript": "^4.1.2",
     "web-stream-tools": "github:openpgpjs/web-stream-tools#5e6cb1a976d50c421091907615cf7cce77ac4f2a",
diff --git a/src/openpgp.js b/src/openpgp.js
index 8fb44e76..46bcc326 100644
--- a/src/openpgp.js
+++ b/src/openpgp.js
@@ -21,7 +21,6 @@ import { Message } from './message';
 import { CleartextMessage } from './cleartext';
 import { generate, reformat } from './key';
 import defaultConfig from './config';
-import './polyfills';
 import util from './util';
 
 let toNativeReadable;
diff --git a/src/polyfills.js b/src/polyfills.js
deleted file mode 100644
index 7183e0f5..00000000
--- a/src/polyfills.js
+++ /dev/null
@@ -1,10 +0,0 @@
-if (typeof TextEncoder === 'undefined') {
-  const nodeUtil = require('util') || {};
-  globalThis.TextEncoder = nodeUtil.TextEncoder;
-  globalThis.TextDecoder = nodeUtil.TextDecoder;
-}
-if (typeof TextEncoder === 'undefined') {
-  const textEncoding = require('text-encoding-utf-8');
-  globalThis.TextEncoder = textEncoding.TextEncoder;
-  globalThis.TextDecoder = textEncoding.TextDecoder;
-}