diff --git a/.eslintignore b/.eslintignore
index fef8e6b32..fe0098417 100644
--- a/.eslintignore
+++ b/.eslintignore
@@ -176,6 +176,7 @@ ReactNativeClient/lib/components/screens/UpgradeSyncTargetScreen.js
 ReactNativeClient/lib/hooks/useEffectDebugger.js
 ReactNativeClient/lib/hooks/useImperativeHandlerDebugger.js
 ReactNativeClient/lib/hooks/usePrevious.js
+ReactNativeClient/lib/hooks/usePropsDebugger.js
 ReactNativeClient/lib/joplin-renderer/MdToHtml/rules/checkbox.js
 ReactNativeClient/lib/joplin-renderer/MdToHtml/rules/fence.js
 ReactNativeClient/lib/joplin-renderer/MdToHtml/rules/mermaid.js
@@ -183,6 +184,7 @@ ReactNativeClient/lib/joplin-renderer/MdToHtml/rules/sanitize_html.js
 ReactNativeClient/lib/JoplinServerApi.js
 ReactNativeClient/lib/ntpDate.js
 ReactNativeClient/lib/services/CommandService.js
+ReactNativeClient/lib/services/debug/populateDatabase.js
 ReactNativeClient/lib/services/keychain/KeychainService.js
 ReactNativeClient/lib/services/keychain/KeychainServiceDriver.dummy.js
 ReactNativeClient/lib/services/keychain/KeychainServiceDriver.mobile.js
diff --git a/.gitignore b/.gitignore
index e392a018e..499227ffe 100644
--- a/.gitignore
+++ b/.gitignore
@@ -169,6 +169,7 @@ ReactNativeClient/lib/components/screens/UpgradeSyncTargetScreen.js
 ReactNativeClient/lib/hooks/useEffectDebugger.js
 ReactNativeClient/lib/hooks/useImperativeHandlerDebugger.js
 ReactNativeClient/lib/hooks/usePrevious.js
+ReactNativeClient/lib/hooks/usePropsDebugger.js
 ReactNativeClient/lib/joplin-renderer/MdToHtml/rules/checkbox.js
 ReactNativeClient/lib/joplin-renderer/MdToHtml/rules/fence.js
 ReactNativeClient/lib/joplin-renderer/MdToHtml/rules/mermaid.js
@@ -176,6 +177,7 @@ ReactNativeClient/lib/joplin-renderer/MdToHtml/rules/sanitize_html.js
 ReactNativeClient/lib/JoplinServerApi.js
 ReactNativeClient/lib/ntpDate.js
 ReactNativeClient/lib/services/CommandService.js
+ReactNativeClient/lib/services/debug/populateDatabase.js
 ReactNativeClient/lib/services/keychain/KeychainService.js
 ReactNativeClient/lib/services/keychain/KeychainServiceDriver.dummy.js
 ReactNativeClient/lib/services/keychain/KeychainServiceDriver.mobile.js
diff --git a/ElectronClient/app.js b/ElectronClient/app.js
index 9a53d832e..e32e603c4 100644
--- a/ElectronClient/app.js
+++ b/ElectronClient/app.js
@@ -34,6 +34,7 @@ const KeymapService = require('lib/services/KeymapService').default;
 const TemplateUtils = require('lib/TemplateUtils');
 const CssUtils = require('lib/CssUtils');
 const resourceEditWatcherReducer = require('lib/services/ResourceEditWatcher/reducer').default;
+// const populateDatabase = require('lib/services/debug/populateDatabase').default;
 const versionInfo = require('lib/versionInfo').default;
 
 const commands = [
@@ -1109,7 +1110,7 @@ class Application extends BaseApplication {
 		try {
 			await keymapService.loadCustomKeymap(`${dir}/keymap-desktop.json`);
 		} catch (err) {
-			bridge().showErrorMessageBox(err.message);
+			reg.logger().error(err.message);
 		}
 
 		AlarmService.setDriver(new AlarmServiceDriverNode({ appName: packageInfo.build.appId }));
@@ -1267,6 +1268,8 @@ class Application extends BaseApplication {
 		};
 
 		bridge().addEventListener('nativeThemeUpdated', this.bridge_nativeThemeUpdated);
+
+		// await populateDatabase(reg.db());
 	}
 
 }
diff --git a/ElectronClient/gui/SideBar/SideBar.tsx b/ElectronClient/gui/SideBar/SideBar.tsx
index d36ac59e6..b73fc77c0 100644
--- a/ElectronClient/gui/SideBar/SideBar.tsx
+++ b/ElectronClient/gui/SideBar/SideBar.tsx
@@ -45,6 +45,50 @@ const commands = [
 	require('./commands/focusElementSideBar'),
 ];
 
+function ExpandIcon(props:any) {
+	const theme = themeStyle(props.themeId);
+	const style:any = { width: 16, maxWidth: 16, opacity: 0.5, fontSize: Math.round(theme.toolbarIconSize * 0.8), display: 'flex', justifyContent: 'center' };
+	if (!props.isVisible) style.visibility = 'hidden';
+	return <i className={props.isExpanded ? 'fas fa-caret-down' : 'fas fa-caret-right'} style={style}></i>;
+}
+
+function ExpandLink(props:any) {
+	return props.hasChildren ? (
+		<StyledExpandLink href="#" data-folder-id={props.folderId} onClick={props.onFolderToggleClick_}>
+			<ExpandIcon themeId={props.themeId} isVisible={true} isExpanded={props.isExpanded}/>
+		</StyledExpandLink>
+	) : (
+		<StyledExpandLink><ExpandIcon themeId={props.themeId} isVisible={false} isExpanded={false}/></StyledExpandLink>
+	);
+}
+
+function FolderItem(props:any) {
+	const { hasChildren, isExpanded, depth, selected, folderId, folderTitle, anchorRef, noteCount, onFolderDragStart_, onFolderDragOver_, onFolderDrop_, itemContextMenu, folderItem_click, onFolderToggleClick_ } = props;
+
+	return (
+		<StyledListItem depth={depth} selected={selected} className={`list-item-container list-item-depth-${depth}`} onDragStart={onFolderDragStart_} onDragOver={onFolderDragOver_} onDrop={onFolderDrop_} draggable={true} data-folder-id={folderId}>
+			<ExpandLink themeId={props.themeId} hasChildren={hasChildren} folderId={folderId} onClick={onFolderToggleClick_} isExpanded={isExpanded}/>
+			<StyledListItemAnchor
+				ref={anchorRef}
+				className="list-item"
+				isConflictFolder={folderId === Folder.conflictFolderId()}
+				href="#"
+				selected={selected}
+				data-id={folderId}
+				data-type={BaseModel.TYPE_FOLDER}
+				onContextMenu={itemContextMenu}
+				data-folder-id={folderId}
+				onClick={() => {
+					folderItem_click(folderId);
+				}}
+				onDoubleClick={onFolderToggleClick_}
+			>
+				{folderTitle} { noteCount && <StyledNoteCount>{noteCount}</StyledNoteCount>}
+			</StyledListItemAnchor>
+		</StyledListItem>
+	);
+}
+
 class SideBarComponent extends React.Component<Props, State> {
 
 	private folderItemsOrder_:any[] = [];
@@ -68,8 +112,18 @@ class SideBarComponent extends React.Component<Props, State> {
 		this.onAllNotesClick_ = this.onAllNotesClick_.bind(this);
 		this.header_contextMenu = this.header_contextMenu.bind(this);
 		this.onAddFolderButtonClick = this.onAddFolderButtonClick.bind(this);
+		this.folderItem_click = this.folderItem_click.bind(this);
 	}
 
+	// componentDidUpdate(prevProps:any, _prevState:any) {
+	// 	const props = this.props as any;
+	// 	for (const k in this.props) {
+	// 		if (prevProps[k] !== props[k]) {
+	// 			console.info('Props', k, props[k]);
+	// 		}
+	// 	}
+	// }
+
 	onFolderDragStart_(event:any) {
 		const folderId = event.currentTarget.getAttribute('data-folder-id');
 		if (!folderId) return;
@@ -257,10 +311,10 @@ class SideBarComponent extends React.Component<Props, State> {
 		menu.popup(bridge().window());
 	}
 
-	folderItem_click(folder:any) {
+	folderItem_click(folderId:string) {
 		this.props.dispatch({
 			type: 'FOLDER_SELECT',
-			id: folder ? folder.id : null,
+			id: folderId ? folderId : null,
 		});
 	}
 
@@ -321,41 +375,26 @@ class SideBarComponent extends React.Component<Props, State> {
 	}
 
 	renderFolderItem(folder:any, selected:boolean, hasChildren:boolean, depth:number) {
-		const isExpanded = this.props.collapsedFolderIds.indexOf(folder.id) < 0;
-		const expandIcon = this.renderExpandIcon(isExpanded, hasChildren);
-		const expandLink = hasChildren ? (
-			<StyledExpandLink href="#" data-folder-id={folder.id} onClick={this.onFolderToggleClick_}>
-				{expandIcon}
-			</StyledExpandLink>
-		) : (
-			<StyledExpandLink>{expandIcon}</StyledExpandLink>
-		);
-
 		const anchorRef = this.anchorItemRef('folder', folder.id);
-		const noteCount = folder.note_count ? this.renderNoteCount(folder.note_count) : '';
 
-		return (
-			<StyledListItem depth={depth} selected={selected} className={`list-item-container list-item-depth-${depth}`} key={folder.id} onDragStart={this.onFolderDragStart_} onDragOver={this.onFolderDragOver_} onDrop={this.onFolderDrop_} draggable={true} data-folder-id={folder.id}>
-				{expandLink}
-				<StyledListItemAnchor
-					ref={anchorRef}
-					className="list-item"
-					isConflictFolder={folder.id === Folder.conflictFolderId()}
-					href="#"
-					selected={selected}
-					data-id={folder.id}
-					data-type={BaseModel.TYPE_FOLDER}
-					onContextMenu={(event:any) => this.itemContextMenu(event)}
-					data-folder-id={folder.id}
-					onClick={() => {
-						this.folderItem_click(folder);
-					}}
-					onDoubleClick={this.onFolderToggleClick_}
-				>
-					{Folder.displayTitle(folder)} {noteCount}
-				</StyledListItemAnchor>
-			</StyledListItem>
-		);
+		return <FolderItem
+			key={folder.id}
+			folderId={folder.id}
+			folderTitle={Folder.displayTitle(folder)}
+			themeId={this.props.themeId}
+			depth={depth}
+			selected={selected}
+			isExpanded={this.props.collapsedFolderIds.indexOf(folder.id) < 0}
+			hasChildren={hasChildren}
+			anchorRef={anchorRef}
+			noteCount={folder.note_count}
+			onFolderDragStart_={this.onFolderDragStart_}
+			onFolderDragOver_={this.onFolderDragOver_}
+			onFolderDrop_={this.onFolderDrop_}
+			itemContextMenu={this.itemContextMenu}
+			folderItem_click={this.folderItem_click}
+			onFolderToggleClick_={this.onFolderToggleClick_}
+		/>;
 	}
 
 	renderTag(tag:any, selected:boolean) {
diff --git a/ReactNativeClient/lib/database.js b/ReactNativeClient/lib/database.js
index a6d296fe9..32d9db6cc 100644
--- a/ReactNativeClient/lib/database.js
+++ b/ReactNativeClient/lib/database.js
@@ -9,6 +9,8 @@ class Database {
 		this.logger_ = new Logger();
 		this.logExcludedQueryTypes_ = [];
 		this.batchTransactionMutex_ = new Mutex();
+		this.profilingEnabled_ = false;
+		this.queryId_ = 1;
 	}
 
 	setLogExcludedQueryTypes(v) {
@@ -71,10 +73,30 @@ class Database {
 
 		let waitTime = 50;
 		let totalWaitTime = 0;
+		const callStartTime = Date.now();
+		let profilingTimeoutId = null;
 		while (true) {
 			try {
 				this.logQuery(sql, params);
+
+				const queryId = this.queryId_++;
+				if (this.profilingEnabled_) {
+					console.info(`SQL START ${queryId}`, sql, params);
+
+					profilingTimeoutId = setInterval(() => {
+						console.warn(`SQL ${queryId} has been running for ${Date.now() - callStartTime}: ${sql}`);
+					}, 3000);
+				}
+
 				const result = await this.driver()[callName](sql, params);
+
+				if (this.profilingEnabled_) {
+					clearInterval(profilingTimeoutId);
+					profilingTimeoutId = null;
+					const elapsed = Date.now() - callStartTime;
+					if (elapsed > 10) console.info(`SQL END ${queryId}`, elapsed, sql, params);
+				}
+
 				return result; // No exception was thrown
 			} catch (error) {
 				if (error && (error.code == 'SQLITE_IOERR' || error.code == 'SQLITE_BUSY')) {
@@ -89,6 +111,8 @@ class Database {
 				} else {
 					throw this.sqliteErrorToJsError(error, sql, params);
 				}
+			} finally {
+				if (profilingTimeoutId) clearInterval(profilingTimeoutId);
 			}
 		}
 	}
diff --git a/ReactNativeClient/lib/hooks/usePropsDebugger.ts b/ReactNativeClient/lib/hooks/usePropsDebugger.ts
new file mode 100644
index 000000000..a4de438fa
--- /dev/null
+++ b/ReactNativeClient/lib/hooks/usePropsDebugger.ts
@@ -0,0 +1,13 @@
+import useEffectDebugger from './useEffectDebugger';
+
+export default function usePropsDebugger(effectHook:any, props:any) {
+	const dependencies:any[] = [];
+	const dependencyNames:string[] = [];
+
+	for (const k in props) {
+		dependencies.push(props[k]);
+		dependencyNames.push(k);
+	}
+
+	useEffectDebugger(effectHook, dependencies, dependencyNames);
+}
diff --git a/ReactNativeClient/lib/models/BaseItem.js b/ReactNativeClient/lib/models/BaseItem.js
index 08bd89d1f..ffe2702bd 100644
--- a/ReactNativeClient/lib/models/BaseItem.js
+++ b/ReactNativeClient/lib/models/BaseItem.js
@@ -156,6 +156,8 @@ class BaseItem extends BaseModel {
 	}
 
 	static async loadItemsByIds(ids) {
+		if (!ids.length) return [];
+
 		const classes = this.syncItemClassNames();
 		let output = [];
 		for (let i = 0; i < classes.length; i++) {
diff --git a/ReactNativeClient/lib/models/Tag.js b/ReactNativeClient/lib/models/Tag.js
index 2bb506fa3..11dd720c4 100644
--- a/ReactNativeClient/lib/models/Tag.js
+++ b/ReactNativeClient/lib/models/Tag.js
@@ -109,6 +109,7 @@ class Tag extends BaseItem {
 
 	static async tagsByNoteId(noteId) {
 		const tagIds = await NoteTag.tagIdsByNoteId(noteId);
+		if (!tagIds.length) return [];
 		return this.modelSelectAll(`SELECT * FROM tags WHERE id IN ("${tagIds.join('","')}")`);
 	}
 
diff --git a/ReactNativeClient/lib/services/debug/populateDatabase.ts b/ReactNativeClient/lib/services/debug/populateDatabase.ts
new file mode 100644
index 000000000..5a1a43002
--- /dev/null
+++ b/ReactNativeClient/lib/services/debug/populateDatabase.ts
@@ -0,0 +1,56 @@
+const Folder = require('lib/models/Folder');
+const Note = require('lib/models/Note');
+
+function randomIndex(array:any[]):number {
+	return Math.round(Math.random() * (array.length - 1));
+}
+
+export default async function populateDatabase(db:any) {
+	await db.clearForTesting();
+
+	const folderCount = 2000;
+	const noteCount = 20000;
+
+	const createdFolderIds:string[] = [];
+	const createdNoteIds:string[] = [];
+
+	for (let i = 0; i < folderCount; i++) {
+		const folder:any = {
+			title: `folder${i}`,
+		};
+
+		const isRoot = Math.random() <= 0.1 || i === 0;
+
+		if (!isRoot) {
+			const parentIndex = randomIndex(createdFolderIds);
+			folder.parent_id = createdFolderIds[parentIndex];
+		}
+
+		const savedFolder = await Folder.save(folder);
+		createdFolderIds.push(savedFolder.id);
+
+		console.info(`Folders: ${i} / ${folderCount}`);
+	}
+
+	let noteBatch = [];
+	for (let i = 0; i < noteCount; i++) {
+		const note:any = { title: `note${i}`, body: `This is note num. ${i}` };
+		const parentIndex = randomIndex(createdFolderIds);
+		note.parent_id = createdFolderIds[parentIndex];
+
+		noteBatch.push(Note.save(note, { dispatchUpdateAction: false }).then((savedNote:any) => {
+			createdNoteIds.push(savedNote.id);
+			console.info(`Notes: ${i} / ${noteCount}`);
+		}));
+
+		if (noteBatch.length > 1000) {
+			await Promise.all(noteBatch);
+			noteBatch = [];
+		}
+	}
+
+	if (noteBatch.length) {
+		await Promise.all(noteBatch);
+		noteBatch = [];
+	}
+}