diff --git a/src/renderer/component/common/markdown-preview.jsx b/src/renderer/component/common/markdown-preview.jsx
index b00ae7025..78af2273d 100644
--- a/src/renderer/component/common/markdown-preview.jsx
+++ b/src/renderer/component/common/markdown-preview.jsx
@@ -6,25 +6,34 @@ import remarkEmoji from 'remark-emoji';
 import ExternalLink from 'component/externalLink';
 import defaultSchema from 'hast-util-sanitize/lib/github.json';
 
+type MarkdownProps = {
+  content: ?string,
+  promptLinks?: boolean,
+};
+
+type SimpleLinkProps = {
+  href?: string,
+  title?: string,
+  children?: React.Node,
+};
+
+const SimpleLink = (props: SimpleLinkProps) => {
+  const { href, title, children } = props;
+  return (
+    <a href={href} title={title}>
+      {children}
+    </a>
+  );
+};
+
 // Use github sanitation schema
 const schema = { ...defaultSchema };
 
 // Extend sanitation schema to support lbry protocol
 schema.protocols.href[3] = 'lbry';
 
-type MarkdownProps = {
-  content: string,
-  promptLinks?: boolean,
-};
-
-const SimpleLink = ({ href, title, children }) => (
-  <a href={href} title={title}>
-    {children}
-  </a>
-);
-
 const MarkdownPreview = (props: MarkdownProps) => {
-  const { content, externalLinks, promptLinks } = props;
+  const { content, promptLinks } = props;
   const remarkOptions = {
     sanitize: schema,
     remarkReactComponents: {
diff --git a/src/renderer/component/fileRender/view.jsx b/src/renderer/component/fileRender/view.jsx
index b9901564e..80a3236a5 100644
--- a/src/renderer/component/fileRender/view.jsx
+++ b/src/renderer/component/fileRender/view.jsx
@@ -10,11 +10,11 @@ import HtmlViewer from 'component/viewers/htmlViewer';
 type Props = {
   mediaType: string,
   source: {
+    stream: string => void,
     fileName: string,
     fileType: string,
+    contentType: string,
     downloadPath: string,
-    stream: opts => void,
-    blob: callback => void,
   },
   currentTheme: string,
 };
diff --git a/src/renderer/component/viewers/codeViewer.jsx b/src/renderer/component/viewers/codeViewer.jsx
index 1d5164468..af6ea8fc0 100644
--- a/src/renderer/component/viewers/codeViewer.jsx
+++ b/src/renderer/component/viewers/codeViewer.jsx
@@ -22,12 +22,12 @@ import 'codemirror/mode/javascript/javascript';
 
 type Props = {
   theme: string,
-  value: string,
+  value: ?string,
   contentType: string,
 };
 
 class CodeViewer extends React.PureComponent<Props> {
-  constructor(props) {
+  constructor(props: Props) {
     super(props);
     this.codeMirror = null;
     this.textarea = React.createRef();
@@ -54,6 +54,8 @@ class CodeViewer extends React.PureComponent<Props> {
     this.codeMirror.on('contextmenu', openSnippetMenu);
   }
 
+  codeMirror: any;
+
   render() {
     const { value } = this.props;
     return (
diff --git a/src/renderer/component/viewers/documentViewer.jsx b/src/renderer/component/viewers/documentViewer.jsx
index 608d34873..ed309236d 100644
--- a/src/renderer/component/viewers/documentViewer.jsx
+++ b/src/renderer/component/viewers/documentViewer.jsx
@@ -8,19 +8,25 @@ import MarkdownPreview from 'component/common/markdown-preview';
 type Props = {
   theme: string,
   source: {
-    stream: opts => void,
+    stream: string => any,
     fileType: string,
     contentType: string,
   },
 };
 
-class DocumentViewer extends React.PureComponent<Props> {
-  constructor(props) {
+type State = {
+  error: boolean,
+  loading: boolean,
+  content: ?string,
+};
+
+class DocumentViewer extends React.PureComponent<Props, State> {
+  constructor(props: Props) {
     super(props);
     this.state = {
-      error: null,
-      content: null,
+      error: false,
       loading: true,
+      content: null,
     };
   }
 
@@ -38,13 +44,14 @@ class DocumentViewer extends React.PureComponent<Props> {
       this.setState({ content: data, loading: false });
     });
 
-    stream.on('error', error => {
+    stream.on('error', () => {
       this.setState({ error: true, loading: false });
     });
   }
 
-  renderDocument(content = null) {
+  renderDocument() {
     let viewer = null;
+    const { content } = this.state;
     const { source, theme } = this.props;
     const { fileType, contentType } = source;
     const markdownType = ['md', 'markdown'];
@@ -70,7 +77,7 @@ class DocumentViewer extends React.PureComponent<Props> {
       <div className="file-render__viewer document-viewer">
         {loading && !error && <LoadingScreen status={loadingMessage} spinner />}
         {error && <LoadingScreen status={errorMessage} spinner={!error} />}
-        {isReady && this.renderDocument(content)}
+        {isReady && this.renderDocument()}
       </div>
     );
   }
diff --git a/src/renderer/component/viewers/docxViewer.jsx b/src/renderer/component/viewers/docxViewer.jsx
index 9959678c5..790269fe6 100644
--- a/src/renderer/component/viewers/docxViewer.jsx
+++ b/src/renderer/component/viewers/docxViewer.jsx
@@ -10,11 +10,17 @@ type Props = {
   source: string,
 };
 
-class DocxViewer extends React.PureComponent<Props> {
-  constructor(props) {
+type State = {
+  error: boolean,
+  loading: boolean,
+  content: ?string,
+};
+
+class DocxViewer extends React.PureComponent<Props, State> {
+  constructor(props: Props) {
     super(props);
     this.state = {
-      error: null,
+      error: false,
       content: null,
       loading: true,
     };
@@ -46,7 +52,7 @@ class DocxViewer extends React.PureComponent<Props> {
         const markdown = breakdance.render(result.value);
         this.setState({ content: markdown, loading: false });
       })
-      .catch(error => {
+      .catch(() => {
         this.setState({ error: true, loading: false });
       })
       .done();
diff --git a/src/renderer/component/viewers/pdfViewer.jsx b/src/renderer/component/viewers/pdfViewer.jsx
index ce0a2095a..4f15ec315 100644
--- a/src/renderer/component/viewers/pdfViewer.jsx
+++ b/src/renderer/component/viewers/pdfViewer.jsx
@@ -7,11 +7,13 @@ type Props = {
 };
 
 class PdfViewer extends React.PureComponent<Props> {
-  constructor(props) {
+  constructor(props: Props) {
     super(props);
     this.viewer = React.createRef();
   }
 
+  viewer: { current: any };
+
   render() {
     const { source } = this.props;
     return (