diff --git a/Telegram/SourceFiles/facades.h b/Telegram/SourceFiles/facades.h
index 67fed2a36..fb4ceaa70 100644
--- a/Telegram/SourceFiles/facades.h
+++ b/Telegram/SourceFiles/facades.h
@@ -23,10 +23,6 @@ Copyright (c) 2014-2017 John Preston, https://desktop.telegram.org
 #include "base/type_traits.h"
 #include "base/observer.h"
 
-namespace Window {
-class LayerWidget;
-} // namespace Window
-
 class BoxContent;
 
 namespace InlineBots {
diff --git a/Telegram/SourceFiles/mainwindow.h b/Telegram/SourceFiles/mainwindow.h
index 7a46d6aca..f8be53177 100644
--- a/Telegram/SourceFiles/mainwindow.h
+++ b/Telegram/SourceFiles/mainwindow.h
@@ -37,6 +37,7 @@ class ClearManager;
 } // namespace Local
 
 namespace Window {
+class LayerWidget;
 class LayerStackWidget;
 class SectionMemento;
 struct SectionShow;
diff --git a/Telegram/SourceFiles/window/window_controller.h b/Telegram/SourceFiles/window/window_controller.h
index 2aeb884a3..72e9001e7 100644
--- a/Telegram/SourceFiles/window/window_controller.h
+++ b/Telegram/SourceFiles/window/window_controller.h
@@ -27,6 +27,8 @@ class MainWidget;
 
 namespace Window {
 
+class LayerWidget;
+
 enum class GifPauseReason {
 	Any           = 0,
 	InlineResults = (1 << 0),
diff --git a/docs/building-cmake.md b/docs/building-cmake.md
index d04b0b39b..05e5865f9 100644
--- a/docs/building-cmake.md
+++ b/docs/building-cmake.md
@@ -2,7 +2,7 @@
 
 ### Prepare folder
 
-Choose an empty folder for the future build, for example **/home/user/TBuild**. It will be named ***BuildPath*** in the rest of this document. Create a ***BuildPath*/Libraries** folder there. All commands will be launched from Terminal.
+Choose an empty folder for the future build, for example **/home/user/TBuild**. It will be named ***BuildPath*** in the rest of this document.
 
 ### Install software and required packages
 
@@ -12,11 +12,13 @@ You will need GCC 7.2 and CMake 3.2 installed. To install them and all the requi
     sudo add-apt-repository ppa:ubuntu-toolchain-r/test
     sudo add-apt-repository ppa:george-edison55/cmake-3.x
     sudo apt-get update
-    sudo apt-get install gcc-7 g++-7
+    sudo apt-get install gcc-7 g++-7 cmake
     sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-7 60
     sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-7 60
+    sudo add-apt-repository --remove ppa:ubuntu-toolchain-r/test
+    sudo add-apt-repository --remove ppa:george-edison55/cmake-3.x
 
-    sudo apt-get install git libexif-dev liblzma-dev libz-dev libssl-dev libappindicator-dev libunity-dev libicu-dev libdee-dev libdrm-dev dh-autoreconf autoconf automake build-essential libass-dev libfreetype6-dev libgpac-dev libsdl1.2-dev libtheora-dev libtool libva-dev libvdpau-dev libvorbis-dev libxcb1-dev libxcb-image0-dev libxcb-shm0-dev libxcb-xfixes0-dev libxcb-keysyms1-dev libxcb-icccm4-dev libxcb-render-util0-dev libxcb-util0-dev libxrender-dev libasound-dev libpulse-dev libxcb-sync0-dev libxcb-randr0-dev libx11-xcb-dev libffi-dev pkg-config texi2html zlib1g-dev yasm cmake xutils-dev bison python-xcbgen
+    sudo apt-get install git libexif-dev liblzma-dev libz-dev libssl-dev libappindicator-dev libunity-dev libicu-dev libdee-dev libdrm-dev dh-autoreconf autoconf automake build-essential libass-dev libfreetype6-dev libgpac-dev libsdl1.2-dev libtheora-dev libtool libva-dev libvdpau-dev libvorbis-dev libxcb1-dev libxcb-image0-dev libxcb-shm0-dev libxcb-xfixes0-dev libxcb-keysyms1-dev libxcb-icccm4-dev libxcb-render-util0-dev libxcb-util0-dev libxrender-dev libasound-dev libpulse-dev libxcb-sync0-dev libxcb-randr0-dev libx11-xcb-dev libffi-dev libncurses5-dev pkg-config texi2html zlib1g-dev yasm cmake xutils-dev bison python-xcbgen
 
 You can set the multithreaded make parameter by running