diff --git a/src/helpers/random.ts b/src/helpers/random.ts
index 0f76df4e..ede11304 100644
--- a/src/helpers/random.ts
+++ b/src/helpers/random.ts
@@ -4,11 +4,17 @@
  * https://github.com/morethanwords/tweb/blob/master/LICENSE
  */
 
-export function nextRandomInt(maxValue: number) {
-  return Math.floor(Math.random() * maxValue);
+const arrays = {
+  8: new Uint8Array(1),
+  16: new Uint16Array(1),
+  32: new Uint32Array(1),
+};
+export function nextRandomUint(bits: 8 | 16 | 32) {
+  const array = arrays[bits];
+  crypto.getRandomValues(array);
+  return array[0];
 }
 
 export function randomLong() {
-  return '' + nextRandomInt(0xFFFFFFFF) + nextRandomInt(0xFFFFFF);
-  //return '' + parseInt(nextRandomInt(0xFFFFFFFF).toString(16) + nextRandomInt(0xFFFFFFFF).toString(16), 16);
+  return '' + nextRandomUint(32) + nextRandomUint(32);
 }
diff --git a/src/lib/appManagers/appStateManager.ts b/src/lib/appManagers/appStateManager.ts
index 34054f99..4c0b19c6 100644
--- a/src/lib/appManagers/appStateManager.ts
+++ b/src/lib/appManagers/appStateManager.ts
@@ -22,7 +22,7 @@ import { Chat } from '../../layer';
 import { isMobile } from '../../helpers/userAgent';
 import DATABASE_STATE from '../../config/databases/state';
 import sessionStorage from '../sessionStorage';
-import { nextRandomInt } from '../../helpers/random';
+import { nextRandomUint } from '../../helpers/random';
 
 const REFRESH_EVERY = 24 * 60 * 60 * 1000; // 1 day
 //const REFRESH_EVERY_WEEK = 24 * 60 * 60 * 1000 * 7; // 7 days
@@ -156,7 +156,7 @@ export const STATE_INIT: State = {
   },
   keepSigned: true,
   chatContextMenuHintWasShown: false,
-  stateId: nextRandomInt(0xFFFFFFFF)
+  stateId: nextRandomUint(32)
 };
 
 const ALL_KEYS = Object.keys(STATE_INIT) as any as Array<keyof State>;
diff --git a/src/lib/crypto/crypto_utils.ts b/src/lib/crypto/crypto_utils.ts
index eee0f1ff..41cb274b 100644
--- a/src/lib/crypto/crypto_utils.ts
+++ b/src/lib/crypto/crypto_utils.ts
@@ -22,7 +22,7 @@ import {str2bigInt, bpe, equalsInt, greater,
 
 import { addPadding } from '../mtproto/bin_utils';
 import { bytesToWordss, bytesFromWordss, bytesToHex, bytesFromHex, convertToUint8Array } from '../../helpers/bytes';
-import { nextRandomInt } from '../../helpers/random';
+import { nextRandomUint } from '../../helpers/random';
 import type { RSAPublicKeyHex } from '../mtproto/rsaKeysManager';
 
 const subtle = typeof(window) !== 'undefined' && 'crypto' in window ? window.crypto.subtle : self.crypto.subtle;
@@ -200,8 +200,8 @@ export function pqPrimeLeemon(what: number[]): [Uint8Array, Uint8Array, number]
   var y = new Array(minLen);
 
   for(i = 0; i < 3; ++i) {
-    q = (nextRandomInt(128) & 15) + 17;
-    copyInt_(x, nextRandomInt(1000000000) + 1);
+    q = (nextRandomUint(8) & 15) + 17;
+    copyInt_(x, nextRandomUint(32) + 1);
     copy_(y, x);
     lim = 1 << (i + 18);
 
diff --git a/src/lib/mtproto/apiFileManager.ts b/src/lib/mtproto/apiFileManager.ts
index fe9bf29c..b2239532 100644
--- a/src/lib/mtproto/apiFileManager.ts
+++ b/src/lib/mtproto/apiFileManager.ts
@@ -16,7 +16,7 @@ import { readBlobAsArrayBuffer } from "../../helpers/blob";
 import { CancellablePromise, deferredPromise } from "../../helpers/cancellablePromise";
 import { notifyAll, notifySomeone } from "../../helpers/context";
 import { getFileNameByLocation } from "../../helpers/fileName";
-import { nextRandomInt } from "../../helpers/random";
+import { randomLong } from "../../helpers/random";
 import { InputFile, InputFileLocation, UploadFile } from "../../layer";
 import { DcId, WorkerTaskVoidTemplate } from "../../types";
 import CacheStorageController from "../cacheStorage";
@@ -524,7 +524,7 @@ export class ApiFileManager {
     const activeDelta = this.getDelta(partSize);
 
     const totalParts = Math.ceil(fileSize / partSize);
-    const fileId: [number, number] = [nextRandomInt(0xFFFFFFFF), nextRandomInt(0xFFFFFFFF)];
+    const fileId = randomLong();
 
     let _part = 0;
 
diff --git a/src/lib/mtproto/bin_utils.ts b/src/lib/mtproto/bin_utils.ts
index 5f4c7555..efb0ebea 100644
--- a/src/lib/mtproto/bin_utils.ts
+++ b/src/lib/mtproto/bin_utils.ts
@@ -11,7 +11,6 @@
 
 import { bufferConcats } from '../../helpers/bytes';
 import { add_, bigInt2str, cmp, leftShift_, str2bigInt } from '../../vendor/leemon';
-import { nextRandomInt } from '../../helpers/random';
 
 /// #if !MTPROTO_WORKER
 // @ts-ignore
@@ -141,15 +140,13 @@ export function addPadding<T extends number[] | ArrayBuffer | Uint8Array>(
   const needPadding = blockSizeAsTotalLength ? blockSize - len : blockSize - (len % blockSize);
   if(needPadding > 0 && needPadding < blockSize) {
     ////console.log('addPadding()', len, blockSize, needPadding);
-    const padding: number[] = new Array(needPadding);
+    const padding = new Uint8Array(needPadding);
     if(zeroes) {
       for(let i = 0; i < needPadding; ++i) {
         padding[i] = 0;
       }
     } else {
-      for(let i = 0; i < needPadding; ++i) {
-        padding[i] = nextRandomInt(255);
-      }
+      padding.randomize();
     }
 
     if(bytes instanceof ArrayBuffer) {
@@ -158,7 +155,7 @@ export function addPadding<T extends number[] | ArrayBuffer | Uint8Array>(
       return (prepend ? bufferConcats(padding, bytes) : bufferConcats(bytes, padding)) as T;
     } else {
       // @ts-ignore
-      return (prepend ? padding.concat(bytes) : bytes.concat(padding)) as T;
+      return (prepend ? [...padding].concat(bytes) : bytes.concat([...padding])) as T;
     }
   }
 
diff --git a/src/lib/mtproto/networker.ts b/src/lib/mtproto/networker.ts
index 627661ec..ad678a76 100644
--- a/src/lib/mtproto/networker.ts
+++ b/src/lib/mtproto/networker.ts
@@ -21,7 +21,7 @@ import { InvokeApiOptions } from '../../types';
 import { longToBytes } from '../crypto/crypto_utils';
 import MTTransport from './transports/transport';
 import { convertToUint8Array, bytesCmp, bytesToHex, bufferConcats } from '../../helpers/bytes';
-import { nextRandomInt } from '../../helpers/random';
+import { nextRandomUint, randomLong } from '../../helpers/random';
 import App from '../../config/app';
 import DEBUG from '../../config/debug';
 import Modes from '../../config/modes';
@@ -549,7 +549,7 @@ export default class MTPNetworker {
     this.checkConnectionTimeout = 0;
   
     const serializer = new TLSerialization({mtproto: true});
-    const pingId = [nextRandomInt(0xFFFFFFFF), nextRandomInt(0xFFFFFFFF)];
+    const pingId = randomLong();
   
     serializer.storeMethod('ping', {
       ping_id: pingId
@@ -1103,7 +1103,7 @@ export default class MTPNetworker {
       this.log.error('wrong length', dataBuffer, canBeLength, message.msg_id);
     } */
 
-    const paddingLength = (16 - (data.getOffset() % 16)) + 16 * (1 + nextRandomInt(5));
+    const paddingLength = (16 - (data.getOffset() % 16)) + 16 * (1 + nextRandomUint(8) % 5);
     const padding = /* (message as any).padding ||  */new Uint8Array(paddingLength).randomize()/* .fill(0) */;
     /* const padding = [167, 148, 207, 226, 86, 192, 193, 57, 124, 153, 174, 145, 159, 1, 5, 70, 127, 157, 
       51, 241, 46, 85, 141, 212, 139, 234, 213, 164, 197, 116, 245, 70, 184, 40, 40, 201, 233, 211, 150, 
diff --git a/src/lib/mtproto/singleInstance.ts b/src/lib/mtproto/singleInstance.ts
index e41c57ef..319028be 100644
--- a/src/lib/mtproto/singleInstance.ts
+++ b/src/lib/mtproto/singleInstance.ts
@@ -10,7 +10,7 @@
  */
 
 import { MOUNT_CLASS_TO } from "../../config/debug";
-import { nextRandomInt } from "../../helpers/random";
+import { nextRandomUint } from "../../helpers/random";
 import { logger } from "../logger";
 import rootScope from "../rootScope";
 import sessionStorage from "../sessionStorage";
@@ -53,7 +53,7 @@ export class SingleInstance {
   }
 
   public reset() {
-    this.instanceID = nextRandomInt(0xFFFFFFFF);
+    this.instanceID = nextRandomUint(32);
     this.masterInstance = false;
     if(this.deactivateTimeout) clearTimeout(this.deactivateTimeout);
     this.deactivateTimeout = 0;
diff --git a/src/lib/mtproto/timeManager.ts b/src/lib/mtproto/timeManager.ts
index 47068870..94f9f364 100644
--- a/src/lib/mtproto/timeManager.ts
+++ b/src/lib/mtproto/timeManager.ts
@@ -11,7 +11,7 @@
 
 import sessionStorage from '../sessionStorage';
 import { longFromInts } from './bin_utils';
-import { nextRandomInt } from '../../helpers/random';
+import { nextRandomUint } from '../../helpers/random';
 import { MOUNT_CLASS_TO } from '../../config/debug';
 import { WorkerTaskVoidTemplate } from '../../types';
 import { notifySomeone } from '../../helpers/context';
@@ -44,7 +44,7 @@ export class TimeManager {
     const timeTicks = Date.now(),
       timeSec = Math.floor(timeTicks / 1000) + this.timeOffset,
       timeMSec = timeTicks % 1000,
-      random = nextRandomInt(0xFFFF);
+      random = nextRandomUint(16);
 
     let messageId: TimeManager['lastMessageId'] = [timeSec, (timeMSec << 21) | (random << 3) | 4];
     if(this.lastMessageId[0] > messageId[0] ||
diff --git a/src/lib/mtproto/transports/padded.ts b/src/lib/mtproto/transports/padded.ts
index f1b6c6fb..a9b6d023 100644
--- a/src/lib/mtproto/transports/padded.ts
+++ b/src/lib/mtproto/transports/padded.ts
@@ -4,7 +4,7 @@
  * https://github.com/morethanwords/tweb/blob/master/LICENSE
  */
 
-import { nextRandomInt } from "../../../helpers/random";
+import { nextRandomUint } from "../../../helpers/random";
 import { IntermediatePacketCodec } from "./intermediate";
 /*  Data packets are aligned to 4bytes. This codec adds random bytes of size
   from 0 to 3 bytes, which are ignored by decoder. */
@@ -13,7 +13,7 @@ class PaddedIntermediatePacketCodec extends IntermediatePacketCodec {
   public obfuscateTag = new Uint8Array([this.tag, this.tag, this.tag, this.tag]);
 
   public encodePacket(data: Uint8Array) {
-    let padding = new Uint8Array(nextRandomInt(3)).randomize();
+    let padding = new Uint8Array(nextRandomUint(8) % 3).randomize();
     let len = data.byteLength + padding.byteLength;
 
     let header = new Uint8Array(new Uint32Array([len]).buffer);
diff --git a/src/vendor/leemon.ts b/src/vendor/leemon.ts
index 1b8a5bf9..8af609f6 100644
--- a/src/vendor/leemon.ts
+++ b/src/vendor/leemon.ts
@@ -345,11 +345,11 @@ export function expand(x: number[], n: number): number[] {
  * @param {number} k
  * @returns {number[]}
  */
-export function randTruePrime(k: number): number[] {
+/* export function randTruePrime(k: number): number[] {
   var ans = int2bigInt(0, k, 0)
   randTruePrime_(ans, k)
   return trim(ans, 1)
-}
+} */
 
 /**
  * return a k-bit random probable prime with probability of error < 2^-80
@@ -358,7 +358,7 @@ export function randTruePrime(k: number): number[] {
  * @param {number} k
  * @returns {number[]}
  */
-export function randProbPrime(k: number): number[] {
+/* export function randProbPrime(k: number): number[] {
   if (k >= 600) return randProbPrimeRounds(k, 2) //numbers from HAC table 4.3
   if (k >= 550) return randProbPrimeRounds(k, 4)
   if (k >= 500) return randProbPrimeRounds(k, 5)
@@ -370,7 +370,7 @@ export function randProbPrime(k: number): number[] {
   if (k >= 150) return randProbPrimeRounds(k, 18)
   if (k >= 100) return randProbPrimeRounds(k, 27)
   return randProbPrimeRounds(k, 40) //number from HAC remark 4.26 (only an estimate)
-}
+} */
 
 /**
  * return a k-bit probable random prime using n rounds of Miller Rabin
@@ -381,7 +381,7 @@ export function randProbPrime(k: number): number[] {
  * @param {number} n
  * @returns {number[]}
  */
-export function randProbPrimeRounds(k: number, n: number): number[] {
+/* export function randProbPrimeRounds(k: number, n: number): number[] {
   var ans, i, divisible, B
   B = 30000 //B is largest prime to use in trial division
   ans = int2bigInt(0, k, 0)
@@ -423,11 +423,7 @@ export function randProbPrimeRounds(k: number, n: number): number[] {
 
     if (!divisible) return ans
   }
-  /*::
-  declare var never: empty
-  return never
-  */
-}
+} */
 
 /**
  * return a new bigInt equal to (x mod n) for bigInts x and n.
@@ -450,11 +446,11 @@ export function mod(x: number[], n: number[]): number[] {
  * @param {number} n
  * @returns {number[]}
  */
-export function addInt(x: number[], n: number): number[] {
+/* export function addInt(x: number[], n: number): number[] {
   var ans = expand(x, x.length + 1)
   addInt_(ans, n)
   return trim(ans, 1)
-}
+} */
 
 /**
  * return x*y for bigInts x and y. This is faster when y<x.
@@ -547,11 +543,11 @@ export function add(x: number[], y: number[]): number[] {
  * @param {number[]} n
  * @returns {(number[] | null)}
  */
-export function inverseMod(x: number[], n: number[]): number[] | null {
+/* export function inverseMod(x: number[], n: number[]): number[] | null {
   var ans = expand(x, n.length)
   var s = inverseMod_(ans, n)
   return s ? trim(ans, 1) : null
-}
+} */
 
 /**
  * return (x*y mod n) for bigInts x,y,n.
@@ -580,7 +576,7 @@ export function multMod(x: number[], y: number[], n: number[]): number[] {
  * @param {number} k
  * @return {void}
  */
-export function randTruePrime_(ans: number[], k: number): void {
+/* export function randTruePrime_(ans: number[], k: number): void {
   var c, m, pm, dd, j, r, B, divisible, z, zz, recSize
   var w
   if (primes.length == 0) primes = findPrimes(30000) //check for divisibility by primes <=30000
@@ -712,7 +708,7 @@ export function randTruePrime_(ans: number[], k: number): void {
       }
     }
   }
-}
+} */
 
 /**
  * Return an n-bit random BigInt (n>=1).  If s=1, then the most significant of those n bits is set to 1.
@@ -722,13 +718,13 @@ export function randTruePrime_(ans: number[], k: number): void {
  * @param {number} s
  * @returns {number[]}
  */
-export function randBigInt(n: number, s: number): number[] {
+/* export function randBigInt(n: number, s: number): number[] {
   var a, b
   a = Math.floor((n - 1) / bpe) + 2 //# array elements to hold the BigInt with a leading 0 element
   b = int2bigInt(0, 0, a)
   randBigInt_(b, n, s)
   return b
-}
+} */
 
 /**
  * Set b to an n-bit random BigInt.  If s=1, then the most significant of those n bits is set to 1.
@@ -741,7 +737,7 @@ export function randBigInt(n: number, s: number): number[] {
  * @param {number} s
  * @return {void}
  */
-export function randBigInt_(b: number[], n: number, s: number): void {
+/* export function randBigInt_(b: number[], n: number, s: number): void {
   var i, a
   for (i = 0; i < b.length; i++) b[i] = 0
   a = Math.floor((n - 1) / bpe) + 1 //# array elements to hold the BigInt
@@ -750,7 +746,7 @@ export function randBigInt_(b: number[], n: number, s: number): void {
   }
   b[a - 1] &= (2 << ((n - 1) % bpe)) - 1
   if (s == 1) b[a - 1] |= 1 << ((n - 1) % bpe)
-}
+} */
 
 /**
  * Return the greatest common divisor of bigInts x and y (each with same number of elements).
@@ -852,7 +848,7 @@ export function GCD_(x: number[], y: number[]): void {
  * @param {number[]} n
  * @returns {(0 | 1)}
  */
-export function inverseMod_(x: number[], n: number[]): Bool {
+/* export function inverseMod_(x: number[], n: number[]): Bool {
   var k = 1 + 2 * Math.max(x.length, n.length)
 
   if (!(x[0] & 1) && !(n[0] & 1)) {
@@ -934,11 +930,7 @@ export function inverseMod_(x: number[], n: number[]): Bool {
       return 1
     }
   }
-  /*::
-  declare var never: empty
-  return never
-  */
-}
+} */
 
 /**
  * return x**(-1) mod n, for integers x and n.
@@ -973,9 +965,9 @@ export function inverseModInt(x: number, n: number): number {
 }
 
 //this deprecated function is for backward compatibility only.
-function inverseModInt_(x: number, n: number) {
+/* function inverseModInt_(x: number, n: number) {
   return inverseModInt(x, n)
-}
+} */
 
 /**
  * Given positive bigInts x and y, change the bigints v, a, and b to positive bigInts such that: