diff --git a/packages/page-explorer/src/BlockInfo/ByHash.tsx b/packages/page-explorer/src/BlockInfo/ByHash.tsx
index 649364f6f7..59f0778165 100644
--- a/packages/page-explorer/src/BlockInfo/ByHash.tsx
+++ b/packages/page-explorer/src/BlockInfo/ByHash.tsx
@@ -3,6 +3,7 @@
 // of the Apache-2.0 license. See the LICENSE file for details.
 
 import { EventRecord, SignedBlock } from '@polkadot/types/interfaces';
+import { KeyedEvent } from '../types';
 
 import React from 'react';
 import { Link } from 'react-router-dom';
@@ -24,7 +25,14 @@ interface Props {
 function BlockByHash ({ className, value }: Props): React.ReactElement<Props> {
   const { t } = useTranslation();
   const { api } = useApi();
-  const events = useCall<EventRecord[]>(api.query.system.events.at, [value], { isSingle: true });
+  const events = useCall<KeyedEvent[]>(api.query.system.events.at, [value], {
+    isSingle: true,
+    transform: (events: EventRecord[]): KeyedEvent[] =>
+      events.map((record) => ({
+        key: `${Date.now()}-${record.hash.toHex()}`,
+        record
+      }))
+  });
   const getBlock = useCall<SignedBlock>(api.rpc.chain.getBlock, [value], { isSingle: true });
   const getHeader = useCall<HeaderExtended>(api.derive.chain.getHeader, [value]);
 
@@ -79,7 +87,7 @@ function BlockByHash ({ className, value }: Props): React.ReactElement<Props> {
             <Column>
               <Events
                 eventClassName='explorer--BlockByHash-block'
-                events={(events || []).filter(({ phase }) => !phase.isApplyExtrinsic)}
+                events={events}
                 label={t('system events')}
               />
             </Column>
diff --git a/packages/page-explorer/src/BlockInfo/Extrinsic.tsx b/packages/page-explorer/src/BlockInfo/Extrinsic.tsx
index 1a4fedcdba..14a6be4342 100644
--- a/packages/page-explorer/src/BlockInfo/Extrinsic.tsx
+++ b/packages/page-explorer/src/BlockInfo/Extrinsic.tsx
@@ -2,7 +2,8 @@
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
-import { BlockNumber, EventRecord, Extrinsic } from '@polkadot/types/interfaces';
+import { BlockNumber, Extrinsic } from '@polkadot/types/interfaces';
+import { KeyedEvent } from '../types';
 
 import React from 'react';
 import styled from 'styled-components';
@@ -16,7 +17,7 @@ import Event from '../Event';
 interface Props {
   blockNumber?: BlockNumber;
   className?: string;
-  events?: EventRecord[];
+  events?: KeyedEvent[];
   index: number;
   value: Extrinsic;
 }
@@ -31,8 +32,8 @@ function getEra ({ era }: Extrinsic, blockNumber?: BlockNumber): [number, number
   return null;
 }
 
-function filterEvents (index: number, events: EventRecord[] = []): EventRecord[] {
-  return events.filter(({ phase }) => phase.isApplyExtrinsic && phase.asApplyExtrinsic.eq(index));
+function filterEvents (index: number, events: KeyedEvent[] = []): KeyedEvent[] {
+  return events.filter(({ record: { phase } }) => phase.isApplyExtrinsic && phase.asApplyExtrinsic.eq(index));
 }
 
 function ExtrinsicDisplay ({ blockNumber, className, events, index, value }: Props): React.ReactElement<Props> {
@@ -76,11 +77,11 @@ function ExtrinsicDisplay ({ blockNumber, className, events, index, value }: Pro
         className='top'
         colSpan={2}
       >
-        {thisEvents.map((event, index) =>
+        {thisEvents.map(({ key, record }) =>
           <Event
             className='explorer--BlockByHash-event'
-            key={`event:${index}`}
-            value={event}
+            key={key}
+            value={record}
           />
         )}
       </td>
diff --git a/packages/page-explorer/src/BlockInfo/Extrinsics.tsx b/packages/page-explorer/src/BlockInfo/Extrinsics.tsx
index 757d3fa263..7fcc52e768 100644
--- a/packages/page-explorer/src/BlockInfo/Extrinsics.tsx
+++ b/packages/page-explorer/src/BlockInfo/Extrinsics.tsx
@@ -2,7 +2,8 @@
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
-import { BlockNumber, EventRecord, Extrinsic } from '@polkadot/types/interfaces';
+import { BlockNumber, Extrinsic } from '@polkadot/types/interfaces';
+import { KeyedEvent } from '../types';
 
 import React, { useMemo } from 'react';
 import { Table } from '@polkadot/react-components';
@@ -13,7 +14,7 @@ import ExtrinsicDisplay from './Extrinsic';
 interface Props {
   blockNumber?: BlockNumber;
   className?: string;
-  events?: EventRecord[];
+  events?: KeyedEvent[];
   label?: React.ReactNode;
   value?: Extrinsic[] | null;
 }
diff --git a/packages/page-explorer/src/Events.tsx b/packages/page-explorer/src/Events.tsx
index ee64bff87e..4efbf7facb 100644
--- a/packages/page-explorer/src/Events.tsx
+++ b/packages/page-explorer/src/Events.tsx
@@ -2,7 +2,7 @@
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
-import { EventRecord } from '@polkadot/types/interfaces';
+import { KeyedEvent } from './types';
 
 import React, { useMemo } from 'react';
 import { Table } from '@polkadot/react-components';
@@ -12,7 +12,7 @@ import { useTranslation } from './translate';
 
 interface Props {
   emptyLabel?: React.ReactNode;
-  events: EventRecord[];
+  events?: KeyedEvent[];
   eventClassName?: string;
   label?: React.ReactNode;
 }
@@ -29,15 +29,15 @@ function Events ({ emptyLabel, eventClassName, events, label }: Props): React.Re
       empty={emptyLabel || t('No events available')}
       header={header}
     >
-      {events
-        .filter(({ event: { method, section } }): boolean => !!method && !!section)
-        .map((event: EventRecord, index): React.ReactNode => (
+      {events && events
+        .filter(({ record: { event: { method, section } } }) => !!method && !!section)
+        .map(({ key, record }): React.ReactNode => (
           <tr
             className={eventClassName}
-            key={`event:${index}`}
+            key={key}
           >
             <td className='overflow'>
-              <Event value={event} />
+              <Event value={record} />
             </td>
           </tr>
         ))
diff --git a/packages/page-explorer/src/Main.tsx b/packages/page-explorer/src/Main.tsx
index c87a7e6c2f..e7737b0137 100644
--- a/packages/page-explorer/src/Main.tsx
+++ b/packages/page-explorer/src/Main.tsx
@@ -28,7 +28,7 @@ function Main ({ events, headers }: Props): React.ReactElement<Props> {
           <BlockHeaders headers={headers} />
         </Column>
         <Column>
-          <Events events={events.map(({ record }) => record)} />
+          <Events events={events} />
         </Column>
       </Columar>
     </>
diff --git a/packages/react-params/src/Param/Account.tsx b/packages/react-params/src/Param/Account.tsx
index 1f4f8f9054..34f2a75e65 100644
--- a/packages/react-params/src/Param/Account.tsx
+++ b/packages/react-params/src/Param/Account.tsx
@@ -4,36 +4,36 @@
 
 import { Props } from '../types';
 
-import React from 'react';
+import React, { useCallback, useState } from 'react';
 import { InputAddress } from '@polkadot/react-components';
 import keyring from '@polkadot/ui-keyring';
 
 import Bare from './Bare';
 
-function onChange ({ onChange }: Props): (_?: string | null) => void {
-  return (value?: string | null): void => {
-    let isValid = false;
+function Account ({ className, defaultValue: { value }, isDisabled, isError, label, onChange, style, withLabel }: Props): React.ReactElement<Props> {
+  const [defaultValue] = useState(value?.toString());
 
-    if (value) {
-      try {
-        keyring.decodeAddress(value);
+  const _onChange = useCallback(
+    (value?: string | null): void => {
+      let isValid = false;
 
-        isValid = true;
-      } catch (err) {
-        console.error(err);
+      if (value) {
+        try {
+          keyring.decodeAddress(value);
+
+          isValid = true;
+        } catch (err) {
+          console.error(err);
+        }
       }
-    }
 
-    onChange && onChange({
-      isValid,
-      value
-    });
-  };
-}
-
-function Account (props: Props): React.ReactElement<Props> {
-  const { className, defaultValue: { value }, isDisabled, isError, label, style, withLabel } = props;
-  const defaultValue = value && value.toString();
+      onChange && onChange({
+        isValid,
+        value
+      });
+    },
+    [onChange]
+  );
 
   return (
     <Bare
@@ -47,7 +47,7 @@ function Account (props: Props): React.ReactElement<Props> {
         isError={isError}
         isInput
         label={label}
-        onChange={onChange(props)}
+        onChange={_onChange}
         placeholder='5...'
         type='allPlus'
         withEllipsis
diff --git a/packages/react-params/src/Param/Amount.tsx b/packages/react-params/src/Param/Amount.tsx
index 2baaa821ea..81792f0b5c 100644
--- a/packages/react-params/src/Param/Amount.tsx
+++ b/packages/react-params/src/Param/Amount.tsx
@@ -5,7 +5,7 @@
 import { Props } from '../types';
 
 import BN from 'bn.js';
-import React from 'react';
+import React, { useCallback, useState } from 'react';
 import { registry } from '@polkadot/react-api';
 import { Input } from '@polkadot/react-components';
 import { ClassOf } from '@polkadot/types';
@@ -13,24 +13,25 @@ import { bnToBn, formatNumber } from '@polkadot/util';
 
 import Bare from './Bare';
 
-function onChange ({ onChange }: Props): (_: string) => void {
-  return function (value: string): void {
-    onChange && onChange({
-      isValid: true,
-      value: new BN(value || 0)
-    });
-  };
-}
+function Amount ({ className, defaultValue: { value }, isDisabled, isError, label, onChange, onEnter, style, withLabel }: Props): React.ReactElement<Props> {
+  const [defaultValue] = useState(
+    isDisabled
+      ? (
+        value instanceof ClassOf(registry, 'AccountIndex')
+          ? value.toString()
+          : formatNumber(value)
+      )
+      : bnToBn((value as number) || 0).toString()
+  );
 
-function Amount (props: Props): React.ReactElement<Props> {
-  const { className, defaultValue: { value }, isDisabled, isError, label, onEnter, style, withLabel } = props;
-  const defaultValue = isDisabled
-    ? (
-      value instanceof ClassOf(registry, 'AccountIndex')
-        ? value.toString()
-        : formatNumber(value)
-    )
-    : bnToBn((value as number) || 0).toString();
+  const _onChange = useCallback(
+    (value: string) =>
+      onChange && onChange({
+        isValid: true,
+        value: new BN(value || 0)
+      }),
+    [onChange]
+  );
 
   return (
     <Bare
@@ -44,7 +45,7 @@ function Amount (props: Props): React.ReactElement<Props> {
         isError={isError}
         label={label}
         min={0}
-        onChange={onChange(props)}
+        onChange={_onChange}
         onEnter={onEnter}
         type={
           isDisabled
diff --git a/packages/react-params/src/Param/BaseBytes.tsx b/packages/react-params/src/Param/BaseBytes.tsx
index 8348bf107e..530446636a 100644
--- a/packages/react-params/src/Param/BaseBytes.tsx
+++ b/packages/react-params/src/Param/BaseBytes.tsx
@@ -43,6 +43,13 @@ function convertInput (value: string): [boolean, Uint8Array] {
 }
 
 function BaseBytes ({ asHex, children, className, defaultValue: { value }, isDisabled, isError, label, length = -1, onChange, onEnter, onEscape, size = 'full', style, validate = defaultValidate, withLabel, withLength }: Props): React.ReactElement<Props> {
+  const [defaultValue] = useState(
+    value
+      ? isHex(value)
+        ? value
+        : u8aToHex(value as Uint8Array, isDisabled ? 256 : -1)
+      : undefined
+  );
   const [isValid, setIsValid] = useState(false);
 
   useEffect((): void => {
@@ -83,14 +90,6 @@ function BaseBytes ({ asHex, children, className, defaultValue: { value }, isDis
     [asHex, length, onChange, validate, withLength]
   );
 
-  const defaultValue = value
-    ? (
-      isHex(value)
-        ? value
-        : u8aToHex(value as Uint8Array, isDisabled ? 256 : -1)
-    )
-    : undefined;
-
   return (
     <Bare
       className={className}
diff --git a/packages/react-params/src/Param/Bool.tsx b/packages/react-params/src/Param/Bool.tsx
index b935d9cc9a..c1657efa8c 100644
--- a/packages/react-params/src/Param/Bool.tsx
+++ b/packages/react-params/src/Param/Bool.tsx
@@ -4,30 +4,36 @@
 
 import { Props } from '../types';
 
-import React from 'react';
+import React, { useCallback, useMemo, useState } from 'react';
 import { Dropdown } from '@polkadot/react-components';
 
+import { useTranslation } from '../translate';
 import Bare from './Bare';
 
-const options = [
-  { text: 'No', value: false },
-  { text: 'Yes', value: true }
-];
+function BoolParam ({ className, defaultValue: { value }, isDisabled, isError, label, onChange, style, withLabel }: Props): React.ReactElement<Props> {
+  const { t } = useTranslation();
+  const [defaultValue] = useState(
+    value instanceof Boolean
+      ? value.valueOf()
+      : value as boolean
+  );
 
-function onChange ({ onChange }: Props): (_: boolean) => void {
-  return function (value: boolean): void {
-    onChange && onChange({
-      isValid: true,
-      value
-    });
-  };
-}
+  const options = useMemo(
+    () => [
+      { text: t('No'), value: false },
+      { text: t('Yes'), value: true }
+    ],
+    [t]
+  );
 
-function BoolParam (props: Props): React.ReactElement<Props> {
-  const { className, defaultValue: { value }, isDisabled, isError, label, style, withLabel } = props;
-  const defaultValue = value instanceof Boolean
-    ? value.valueOf()
-    : value as boolean;
+  const _onChange = useCallback(
+    (value: boolean) =>
+      onChange && onChange({
+        isValid: true,
+        value
+      }),
+    [onChange]
+  );
 
   return (
     <Bare
@@ -40,7 +46,7 @@ function BoolParam (props: Props): React.ReactElement<Props> {
         isDisabled={isDisabled}
         isError={isError}
         label={label}
-        onChange={onChange(props)}
+        onChange={_onChange}
         options={options}
         withEllipsis
         withLabel={withLabel}
diff --git a/packages/react-params/src/Param/Code.tsx b/packages/react-params/src/Param/Code.tsx
index a960456934..dfddb03c6a 100644
--- a/packages/react-params/src/Param/Code.tsx
+++ b/packages/react-params/src/Param/Code.tsx
@@ -4,45 +4,35 @@
 
 import { Props } from '../types';
 
-import React from 'react';
+import React, { useCallback } from 'react';
 
 import Bytes from './Bytes';
 import BytesFile from './File';
 
-function renderDisabled ({ className, defaultValue, isError, label, onEnter, onEscape, style, type, withLabel }: Props): React.ReactNode {
-  return (
-    <Bytes
-      className={className}
-      defaultValue={defaultValue}
-      isError={isError}
-      label={label}
-      onEnter={onEnter}
-      onEscape={onEscape}
-      style={style}
-      type={type}
-      withLabel={withLabel}
-    />
+function Code ({ className, defaultValue, isDisabled, isError, label, onChange, onEnter, onEscape, style, type, withLabel }: Props): React.ReactElement<Props> {
+  // TODO: Validate that we have actual proper WASM code
+  const _onChange = useCallback(
+    (value: Uint8Array) =>
+      onChange && onChange({
+        isValid: value.length !== 0,
+        value
+      }),
+    [onChange]
   );
-}
-
-// TODO: Validate that we have actual proper WASM code
-function onChange ({ onChange }: Props): (_: Uint8Array) => void {
-  return function (value: Uint8Array): void {
-    onChange && onChange({
-      isValid: value.length !== 0,
-      value
-    });
-  };
-}
-
-function Code (props: Props): React.ReactElement<Props> {
-  const { className, defaultValue, isDisabled, isError, label, style, withLabel } = props;
 
   if (isDisabled) {
     return (
-      <>
-        {renderDisabled(props)}
-      </>
+      <Bytes
+        className={className}
+        defaultValue={defaultValue}
+        isError={isError}
+        label={label}
+        onEnter={onEnter}
+        onEscape={onEscape}
+        style={style}
+        type={type}
+        withLabel={withLabel}
+      />
     );
   }
 
@@ -52,7 +42,7 @@ function Code (props: Props): React.ReactElement<Props> {
       defaultValue={defaultValue}
       isError={isError}
       label={label}
-      onChange={onChange(props)}
+      onChange={_onChange}
       style={style}
       withLabel={withLabel}
     />
diff --git a/packages/react-params/src/Param/Moment.tsx b/packages/react-params/src/Param/Moment.tsx
index 74a4a41532..386286020a 100644
--- a/packages/react-params/src/Param/Moment.tsx
+++ b/packages/react-params/src/Param/Moment.tsx
@@ -4,43 +4,32 @@
 
 import { Props, RawParamOnChangeValue } from '../types';
 
-import React from 'react';
+import React, { useCallback } from 'react';
 import { Static } from '@polkadot/react-components';
 
 import Amount from './Amount';
 
-function renderDisabled ({ className, defaultValue, isError, label, style, withLabel }: Props): React.ReactNode {
-  return (
-    <Static
-      className={className}
-      defaultValue={
-        (defaultValue && defaultValue.value)
-          ? defaultValue.value.toString()
-          : ''
-      }
-      isError={isError}
-      label={label}
-      style={style}
-      withLabel={withLabel}
-    />
+function Moment ({ className, defaultValue, isDisabled, isError, label, onChange, onEnter, onEscape, style, type, withLabel }: Props): React.ReactElement<Props> {
+  const _onChange = useCallback(
+    (value: RawParamOnChangeValue) =>
+      onChange && onChange(value),
+    [onChange]
   );
-}
-
-// TODO: Validate that we have actual proper WASM code
-function onChange ({ onChange }: Props): (_: RawParamOnChangeValue) => void {
-  return function (value: RawParamOnChangeValue): void {
-    onChange && onChange(value);
-  };
-}
-
-function Moment (props: Props): React.ReactElement<Props> {
-  const { className, defaultValue, isDisabled, isError, label, onEnter, onEscape, style, type, withLabel } = props;
 
   if (isDisabled) {
     return (
-      <>
-        {renderDisabled(props)}
-      </>
+      <Static
+        className={className}
+        defaultValue={
+          (defaultValue && defaultValue.value)
+            ? defaultValue.value.toString()
+            : ''
+        }
+        isError={isError}
+        label={label}
+        style={style}
+        withLabel={withLabel}
+      />
     );
   }
 
@@ -51,7 +40,7 @@ function Moment (props: Props): React.ReactElement<Props> {
       isDisabled={isDisabled}
       isError={isError}
       label={label}
-      onChange={onChange(props)}
+      onChange={_onChange}
       onEnter={onEnter}
       onEscape={onEscape}
       style={style}
diff --git a/packages/react-params/src/Param/Raw.tsx b/packages/react-params/src/Param/Raw.tsx
index 56b3577ea8..20b21623cb 100644
--- a/packages/react-params/src/Param/Raw.tsx
+++ b/packages/react-params/src/Param/Raw.tsx
@@ -4,24 +4,24 @@
 
 import { Props } from '../types';
 
-import React from 'react';
+import React, { useCallback } from 'react';
 import { Input } from '@polkadot/react-components';
 
 import Bare from './Bare';
 
-function onChange ({ onChange }: Props): (_: string) => void {
-  return function (value: string): void {
-    const isValid = value.length !== 0;
+function Raw ({ className, defaultValue: { value }, isDisabled, isError, label, onChange, onEnter, onEscape, style, withLabel }: Props): React.ReactElement<Props> {
+  const _onChange = useCallback(
+    (value: string): void => {
+      const isValid = value.length !== 0;
 
-    onChange && onChange({
-      isValid,
-      value
-    });
-  };
-}
+      onChange && onChange({
+        isValid,
+        value
+      });
+    },
+    [onChange]
+  );
 
-function Raw (props: Props): React.ReactElement<Props> {
-  const { className, defaultValue: { value }, isDisabled, isError, label, onEnter, onEscape, style, withLabel } = props;
   const defaultValue = value
     ? (value.toHex ? value.toHex() : value)
     : '';
@@ -37,7 +37,7 @@ function Raw (props: Props): React.ReactElement<Props> {
         isDisabled={isDisabled}
         isError={isError}
         label={label}
-        onChange={onChange(props)}
+        onChange={_onChange}
         onEnter={onEnter}
         onEscape={onEscape}
         placeholder='Hex data'
diff --git a/packages/react-params/src/Param/Text.tsx b/packages/react-params/src/Param/Text.tsx
index 61e58e0a57..8b182090b2 100644
--- a/packages/react-params/src/Param/Text.tsx
+++ b/packages/react-params/src/Param/Text.tsx
@@ -4,24 +4,21 @@
 
 import { Props } from '../types';
 
-import React from 'react';
+import React, { useCallback } from 'react';
 import { Input } from '@polkadot/react-components';
 
 import Bare from './Bare';
 
-function onChange ({ onChange }: Props): (_: string) => void {
-  return function (value: string): void {
-    const isValid = value.length !== 0;
+function Text ({ className, defaultValue: { value }, isDisabled, isError, label, onChange, onEnter, onEscape, style, withLabel }: Props): React.ReactElement<Props> {
+  const _onChange = useCallback(
+    (value: string) =>
+      onChange && onChange({
+        isValid: value.length !== 0,
+        value
+      }),
+    [onChange]
+  );
 
-    onChange && onChange({
-      isValid,
-      value
-    });
-  };
-}
-
-function Text (props: Props): React.ReactElement<Props> {
-  const { className, defaultValue: { value }, isDisabled, isError, label, onEnter, onEscape, style, withLabel } = props;
   const defaultValue = (value || '').toString();
 
   return (
@@ -35,7 +32,7 @@ function Text (props: Props): React.ReactElement<Props> {
         isDisabled={isDisabled}
         isError={isError}
         label={label}
-        onChange={onChange(props)}
+        onChange={_onChange}
         onEnter={onEnter}
         onEscape={onEscape}
         placeholder='<any string>'
diff --git a/packages/react-params/src/Param/VoteThreshold.tsx b/packages/react-params/src/Param/VoteThreshold.tsx
index 2f40a9f05c..2ee7426743 100644
--- a/packages/react-params/src/Param/VoteThreshold.tsx
+++ b/packages/react-params/src/Param/VoteThreshold.tsx
@@ -4,7 +4,7 @@
 
 import { Props } from '../types';
 
-import React from 'react';
+import React, { useCallback } from 'react';
 import { ClassOf } from '@polkadot/types';
 import { registry } from '@polkadot/react-api';
 import { Dropdown } from '@polkadot/react-components';
@@ -26,17 +26,16 @@ export const textMap = options.reduce((textMap, { text, value }): TextMap => {
   return textMap;
 }, {} as unknown as TextMap);
 
-function onChange ({ onChange }: Props): (_: number) => void {
-  return function (value: number): void {
-    onChange && onChange({
-      isValid: true,
-      value
-    });
-  };
-}
+function VoteThresholdParam ({ className, defaultValue: { value }, isDisabled, isError, label, onChange, style, withLabel }: Props): React.ReactElement<Props> {
+  const _onChange = useCallback(
+    (value: number) =>
+      onChange && onChange({
+        isValid: true,
+        value
+      }),
+    [onChange]
+  );
 
-function VoteThresholdParam (props: Props): React.ReactElement<Props> {
-  const { className, defaultValue: { value }, isDisabled, isError, label, style, withLabel } = props;
   const defaultValue = value instanceof ClassOf(registry, 'VoteThreshold')
     ? value.toNumber()
     : bnToBn(value as number).toNumber();
@@ -52,7 +51,7 @@ function VoteThresholdParam (props: Props): React.ReactElement<Props> {
         isDisabled={isDisabled}
         isError={isError}
         label={label}
-        onChange={onChange(props)}
+        onChange={_onChange}
         options={options}
         withLabel={withLabel}
       />