diff --git a/browser_patches/checkout_build_archive_upload.sh b/browser_patches/checkout_build_archive_upload.sh
index f715b72ce0..b343a7f878 100755
--- a/browser_patches/checkout_build_archive_upload.sh
+++ b/browser_patches/checkout_build_archive_upload.sh
@@ -52,9 +52,7 @@ else
 fi
 
 echo "-- preparing checkout"
-# the "do_checkout" script asks if you want to reset existing branch.
-# sure we do!
-yes | ./do_checkout.sh $BROWSER_NAME
+./prepare_checkout.sh $BROWSER_NAME
 echo "-- building"
 ./$BROWSER_NAME/build.sh
 echo "-- archiving to $ZIP_PATH"
diff --git a/browser_patches/do_checkout.sh b/browser_patches/do_checkout.sh
deleted file mode 100755
index dcf15a8d58..0000000000
--- a/browser_patches/do_checkout.sh
+++ /dev/null
@@ -1,131 +0,0 @@
-#!/bin/bash
-set -e
-set +x
-
-trap "cd $(pwd -P)" EXIT
-cd "$(dirname "$0")"
-
-if [[ ($1 == '--help') || ($1 == '-h') ]]; then
-  echo "usage: $(basename $0) [firefox|webkit]"
-  echo
-  echo "Produces a browser checkout ready to be built."
-  echo
-  exit 0
-fi
-
-if [[ $# == 0 ]]; then
-  echo "missing browser: 'firefox' or 'webkit'"
-  echo "try './$(basename $0) --help' for more information"
-  exit 1
-fi
-
-# FRIENDLY_CHECKOUT_PATH is used only for logging.
-FRIENDLY_CHECKOUT_PATH="";
-CHECKOUT_PATH=""
-# Export path is where we put the patches and BASE_REVISION
-REMOTE_URL=""
-BASE_BRANCH=""
-if [[ ("$1" == "firefox") || ("$1" == "firefox/") ]]; then
-  # we always apply our patches atop of beta since it seems to get better
-  # reliability guarantees.
-  BASE_BRANCH="beta"
-  FRIENDLY_CHECKOUT_PATH="//browser_patches/firefox/checkout";
-  CHECKOUT_PATH="$PWD/firefox/checkout"
-  REMOTE_URL="https://github.com/mozilla/gecko-dev"
-elif [[ ("$1" == "webkit") || ("$1" == "webkit/") ]]; then
-  # webkit has only a master branch.
-  BASE_BRANCH="master"
-  FRIENDLY_CHECKOUT_PATH="//browser_patches/webkit/checkout";
-  CHECKOUT_PATH="$PWD/webkit/checkout"
-  REMOTE_URL=""
-  REMOTE_URL="https://github.com/webkit/webkit"
-else
-  echo ERROR: unknown browser - "$1"
-  exit 1
-fi
-
-# if there's no checkout folder - checkout one.
-if ! [[ -d $CHECKOUT_PATH ]]; then
-  echo "-- $FRIENDLY_CHECKOUT_PATH is missing - checking out.."
-  git clone --single-branch --branch $BASE_BRANCH $REMOTE_URL $CHECKOUT_PATH
-else
-  echo "-- checking $FRIENDLY_CHECKOUT_PATH folder - OK"
-fi
-
-# if folder exists but not a git repository - bail out.
-if ! [[ -d $CHECKOUT_PATH/.git ]]; then
-  echo "ERROR: $FRIENDLY_CHECKOUT_PATH is not a git repository! Remove it and re-run the script."
-  exit 1
-else
-  echo "-- checking $FRIENDLY_CHECKOUT_PATH is a git repo - OK"
-fi
-
-# Switch to git repository.
-cd $CHECKOUT_PATH
-
-# Check if git repo is dirty.
-if [[ -n $(git status -s) ]]; then
-  echo "ERROR: $FRIENDLY_CHECKOUT_PATH has dirty GIT state - commit everything and re-run the script."
-  exit 1
-fi
-
-if [[ $(git config --get remote.origin.url) == "$REMOTE_URL" ]]; then
-  echo "-- checking git origin url to point to $REMOTE_URL - OK";
-else
-  echo "ERROR: git origin url DOES NOT point to $REMOTE_URL. Remove $FRIENDLY_CHECKOUT_PATH and re-run the script.";
-  exit 1
-fi
-
-# if there's no "BASE_BRANCH" branch - bail out.
-if ! git show-ref --verify --quiet refs/heads/$BASE_BRANCH; then
-  echo "ERROR: $FRIENDLY_CHECKOUT_PATH/ does not have '$BASE_BRANCH' branch! Remove checkout/ and re-run the script."
-  exit 1
-else
-  echo "-- checking $FRIENDLY_CHECKOUT_PATH has 'beta' branch - OK"
-fi
-
-if ! [[ -z $(git log --oneline origin/$BASE_BRANCH..$BASE_BRANCH) ]]; then
-  echo "ERROR: branch '$BASE_BRANCH' and branch 'origin/$BASE_BRANCH' have diverged - bailing out. Remove checkout/ and re-run the script."
-  exit 1;
-else
-  echo "-- checking that $BASE_BRANCH and origin/$BASE_BRANCH are not diverged - OK"
-fi
-
-git checkout $BASE_BRANCH
-git pull origin $BASE_BRANCH
-
-PINNED_COMMIT=$(cat ../BASE_REVISION)
-if ! git cat-file -e $PINNED_COMMIT^{commit}; then
-  echo "ERROR: $FRIENDLY_CHECKOUT_PATH/ does not include the BASE_REVISION (@$PINNED_COMMIT). Remove checkout/ and re-run the script."
-  exit 1
-else
-  echo "-- checking $FRIENDLY_CHECKOUT_PATH repo has BASE_REVISION (@$PINNED_COMMIT) commit - OK"
-fi
-
-# If there's already a PWDEV branch than we should check if it's fine to reset all changes
-# to it.
-if git show-ref --verify --quiet refs/heads/pwdev; then
-  read -p "Do you want to reset 'PWDEV' branch? (ALL CHANGES WILL BE LOST) Y/n " -n 1 -r
-  echo
-  # if it's not fine to reset branch - bail out.
-  if ! [[ $REPLY =~ ^[Yy]$ ]]; then
-    echo "If you want to keep the branch, than I can't do much! Bailing out!"
-    exit 1
-  else
-    git checkout pwdev
-    git reset --hard $PINNED_COMMIT
-    echo "-- PWDEV now points to BASE_REVISION (@$PINNED_COMMIT)"
-  fi
-else
-  # Otherwise just create a new branch.
-  git checkout -b pwdev
-  git reset --hard $PINNED_COMMIT
-  echo "-- created 'pwdev' branch that points to BASE_REVISION (@$PINNED_COMMIT)."
-fi
-
-echo "-- applying all patches"
-git am ../patches/*
-
-echo
-echo
-echo "DONE. Browser is ready to be built."
diff --git a/browser_patches/export.sh b/browser_patches/export.sh
index 3d89e7c14f..96d0e48049 100755
--- a/browser_patches/export.sh
+++ b/browser_patches/export.sh
@@ -5,10 +5,15 @@ set +x
 trap "cd $(pwd -P)" EXIT
 cd "$(dirname "$0")"
 
+REMOTE_BROWSER_UPSTREAM="browser_upstream"
+BUILD_BRANCH="playwright-build"
+
 if [[ ($1 == '--help') || ($1 == '-h') ]]; then
   echo "usage: export.sh [firefox|webkit] [custom_checkout_path]"
   echo
-  echo "Exports BASE_REVISION and patch from the checkout to browser folder."
+  echo "Exports patch from the current branch of the checkout to browser folder."
+  echo "The checkout has to be 'prepared', meaning that 'prepare_checkout.sh' should be"
+  echo "run against it first."
   echo
   echo "You can optionally specify custom_checkout_path if you have browser checkout somewhere else"
   echo "and wish to export patches from it."
@@ -25,22 +30,17 @@ fi
 # FRIENDLY_CHECKOUT_PATH is used only for logging.
 FRIENDLY_CHECKOUT_PATH="";
 CHECKOUT_PATH=""
-# Export path is where we put the patches and BASE_REVISION
 EXPORT_PATH=""
-BASE_BRANCH=""
 if [[ ("$1" == "firefox") || ("$1" == "firefox/") ]]; then
-  # we always apply our patches atop of beta since it seems to get better
-  # reliability guarantees.
-  BASE_BRANCH="origin/beta"
   FRIENDLY_CHECKOUT_PATH="//browser_patches/firefox/checkout";
   CHECKOUT_PATH="$PWD/firefox/checkout"
   EXPORT_PATH="$PWD/firefox/"
+  source "./firefox/UPSTREAM_CONFIG.sh"
 elif [[ ("$1" == "webkit") || ("$1" == "webkit/") ]]; then
-  # webkit has only a master branch.
-  BASE_BRANCH="origin/master"
   FRIENDLY_CHECKOUT_PATH="//browser_patches/webkit/checkout";
   CHECKOUT_PATH="$PWD/webkit/checkout"
   EXPORT_PATH="$PWD/webkit/"
+  source "./webkit/UPSTREAM_CONFIG.sh"
 else
   echo ERROR: unknown browser to export - "$1"
   exit 1
@@ -72,6 +72,17 @@ fi
 # Switch to git repository.
 cd $CHECKOUT_PATH
 
+# Setting up |$REMOTE_BROWSER_UPSTREAM| remote and fetch the $BASE_BRANCH
+if git remote get-url $REMOTE_BROWSER_UPSTREAM >/dev/null; then
+  if ! [[ $(git remote get-url $REMOTE_BROWSER_UPSTREAM) == "$REMOTE_URL" ]]; then
+    echo "ERROR: remote $REMOTE_BROWSER_UPSTREAM is not pointng to '$REMOTE_URL'! run `prepare_checkout.sh` first"
+    exit 1
+  fi
+else
+  echo "ERROR: checkout does not have $REMOTE_BROWSER_UPSTREAM; run `prepare_checkout.sh` first"
+  exit 1
+fi
+
 # Check if git repo is dirty.
 if [[ -n $(git status -s) ]]; then
   echo "ERROR: $FRIENDLY_CHECKOUT_PATH has dirty GIT state - aborting export."
@@ -81,28 +92,29 @@ else
 fi
 
 CURRENT_BRANCH=$(git rev-parse --abbrev-ref HEAD)
-MERGE_BASE=$(git merge-base $BASE_BRANCH $CURRENT_BRANCH)
+BASE_REVISION=$(git merge-base $REMOTE_BROWSER_UPSTREAM/$BASE_BRANCH $CURRENT_BRANCH)
 echo "=============================================================="
 echo "    Repository:                $FRIENDLY_CHECKOUT_PATH"
-echo "    Changes between branches:  $BASE_BRANCH..$CURRENT_BRANCH"
-echo "    BASE_REVISION:             $MERGE_BASE"
+echo "    Changes between branches:  $REMOTE_BROWSER_UPSTREAM/$BASE_BRANCH..$CURRENT_BRANCH"
+echo "    BASE_REVISION:             $BASE_REIVSION"
 echo
-read -p "Export? Y/n " -n 1 -r
-echo
-# if it's not fine to reset branch - bail out.
-if ! [[ $REPLY =~ ^[Yy]$ ]]; then
-  echo "Exiting."
-  exit 1
-fi
 
-echo $MERGE_BASE > $EXPORT_PATH/BASE_REVISION
-git checkout -b tmpsquash_export_script $MERGE_BASE
+echo $BASE_REIVSION > $EXPORT_PATH/BASE_REVISION
+git checkout -b tmpsquash_export_script $BASE_REIVSION
 git merge --squash $CURRENT_BRANCH
-git commit -am "chore: bootstrap"
+if ! git commit -am "chore: bootstrap"; then
+  echo "No changes!"
+  git checkout $CURRENT_BRANCH
+  git branch -D tmpsquash_export_script
+  exit 0
+fi
 PATCH_NAME=$(git format-patch -1 HEAD)
 mv $PATCH_NAME $EXPORT_PATH/patches/
 git checkout $CURRENT_BRANCH
 git branch -D tmpsquash_export_script
+echo "REMOTE_URL=\"$REMOTE_URL\"
+BASE_BRANCH=\"$BASE_BRANCH\"
+BASE_REVISION=\"$BASE_REIVSION\"" > $EXPORT_PATH/UPSTREAM_CONFIG.sh
 
 # Increment BUILD_NUMBER
 BUILD_NUMBER=$(cat $EXPORT_PATH/BUILD_NUMBER)
diff --git a/browser_patches/firefox/BASE_REVISION b/browser_patches/firefox/BASE_REVISION
deleted file mode 100644
index 37eb8e8658..0000000000
--- a/browser_patches/firefox/BASE_REVISION
+++ /dev/null
@@ -1 +0,0 @@
-46ca28eadfe840021e2ea496fa6b26f924fa135b
diff --git a/browser_patches/firefox/README.md b/browser_patches/firefox/README.md
deleted file mode 100644
index e3368007ed..0000000000
--- a/browser_patches/firefox/README.md
+++ /dev/null
@@ -1,22 +0,0 @@
-# Building Juggler (Linux & Mac)
-
-1. Run `./do_checkout.sh` script. This will create a "checkout" folder with gecko-dev mirror from
-GitHub and apply the PlayWright-specific patches.
-2. Run `./do_build.sh` script to compile browser. Note: you'll need to follow [build instructions](https://developer.mozilla.org/en-US/docs/Mozilla/Developer_guide/Build_Instructions) to setup host environment first.
-
-# Updating `FIREFOX_REVISION` and `//patches/*`
-
-The `./export.sh` script will export a patch that describes all the differences between the current branch in `./checkout`
-and the `beta` branch in `./checkout`.
-
-# Uploading to Azure CDN
-
-Uploading requires having both `AZ_ACCOUNT_KEY` and `AZ_ACCOUNT_NAME` env variables to be defined.
-
-The following sequence of steps will checkout, build and upload build to Azure CDN on both Linux and Mac:
-
-```sh
-$ ./do_checkout.sh
-$ ./build.sh
-$ ./upload.sh
-```
diff --git a/browser_patches/firefox/UPSTREAM_CONFIG.sh b/browser_patches/firefox/UPSTREAM_CONFIG.sh
new file mode 100644
index 0000000000..21d9846f16
--- /dev/null
+++ b/browser_patches/firefox/UPSTREAM_CONFIG.sh
@@ -0,0 +1,3 @@
+REMOTE_URL="https://github.com/mozilla/gecko-dev"
+BASE_BRANCH="beta"
+BASE_REVISION="46ca28eadfe840021e2ea496fa6b26f924fa135b"
diff --git a/browser_patches/firefox/build.sh b/browser_patches/firefox/build.sh
index eadd946aff..07ee3d540f 100755
--- a/browser_patches/firefox/build.sh
+++ b/browser_patches/firefox/build.sh
@@ -6,11 +6,13 @@ trap "cd $(pwd -P)" EXIT
 cd "$(dirname $0)"
 cd "checkout"
 
-if ! [[ $(git rev-parse --abbrev-ref HEAD) == "pwdev" ]]; then
-  echo "ERROR: Cannot build any branch other than PWDEV"
+BUILD_BRANCH="playwright-build"
+
+if ! [[ $(git rev-parse --abbrev-ref HEAD) == "$BUILD_BRANCH" ]]; then
+  echo "ERROR: Cannot build any branch other than $BUILD_BRANCH"
   exit 1;
 else
-  echo "-- checking git branch is PWDEV - OK"
+  echo "-- checking git branch is $BUILD_BRANCH - OK"
 fi
 
 if [[ "$(uname)" == "Darwin" ]]; then
diff --git a/browser_patches/prepare_checkout.sh b/browser_patches/prepare_checkout.sh
new file mode 100755
index 0000000000..542b39e44e
--- /dev/null
+++ b/browser_patches/prepare_checkout.sh
@@ -0,0 +1,108 @@
+#!/bin/bash
+set -e
+set +x
+
+trap "cd $(pwd -P)" EXIT
+cd "$(dirname "$0")"
+
+REMOTE_BROWSER_UPSTREAM="browser_upstream"
+BUILD_BRANCH="playwright-build"
+
+if [[ ($1 == '--help') || ($1 == '-h') ]]; then
+  echo "usage: $(basename $0) [firefox|webkit] [custom_checkout_path]"
+  echo
+  echo "Prepares browser checkout. The checkout is a GIT repository that:"
+  echo "- has a '$REMOTE_BROWSER_UPSTREAM' remote pointing to a REMOTE_URL from UPSTREAM_CONFIG.sh"
+  echo "- has a '$BUILD_BRANCH' branch that is BASE_REVISION with all the patches applied."
+  echo
+  echo "You can optionally specify custom_checkout_path if you want to use some other browser checkout"
+  echo
+  exit 0
+fi
+
+if [[ $# == 0 ]]; then
+  echo "missing browser: 'firefox' or 'webkit'"
+  echo "try './$(basename $0) --help' for more information"
+  exit 1
+fi
+
+# FRIENDLY_CHECKOUT_PATH is used only for logging.
+FRIENDLY_CHECKOUT_PATH="";
+CHECKOUT_PATH=""
+if [[ ("$1" == "firefox") || ("$1" == "firefox/") ]]; then
+  FRIENDLY_CHECKOUT_PATH="//browser_patches/firefox/checkout";
+  CHECKOUT_PATH="$PWD/firefox/checkout"
+  source "./firefox/UPSTREAM_CONFIG.sh"
+elif [[ ("$1" == "webkit") || ("$1" == "webkit/") ]]; then
+  FRIENDLY_CHECKOUT_PATH="//browser_patches/webkit/checkout";
+  CHECKOUT_PATH="$PWD/webkit/checkout"
+  source "./webkit/UPSTREAM_CONFIG.sh"
+else
+  echo ERROR: unknown browser - "$1"
+  exit 1
+fi
+
+# we will use this just for beauty.
+if [[ $# == 2 ]]; then
+  echo "WARNING: using custom checkout path $CHECKOUT_PATH"
+  CHECKOUT_PATH=$2
+  FRIENDLY_CHECKOUT_PATH="<custom_checkout>"
+fi
+
+# if there's no checkout folder - checkout one.
+if ! [[ -d $CHECKOUT_PATH ]]; then
+  echo "-- $FRIENDLY_CHECKOUT_PATH is missing - checking out.."
+  git clone --single-branch --branch $BASE_BRANCH $REMOTE_URL $CHECKOUT_PATH
+else
+  echo "-- checking $FRIENDLY_CHECKOUT_PATH folder - OK"
+fi
+
+# if folder exists but not a git repository - bail out.
+if ! [[ -d $CHECKOUT_PATH/.git ]]; then
+  echo "ERROR: $FRIENDLY_CHECKOUT_PATH is not a git repository! Remove it and re-run the script."
+  exit 1
+else
+  echo "-- checking $FRIENDLY_CHECKOUT_PATH is a git repo - OK"
+fi
+
+# ============== SETTING UP GIT REPOSITORY ==============
+cd $CHECKOUT_PATH
+
+# Bail out if git repo is dirty.
+if [[ -n $(git status -s) ]]; then
+  echo "ERROR: $FRIENDLY_CHECKOUT_PATH has dirty GIT state - commit everything and re-run the script."
+  exit 1
+fi
+
+# Setting up |$REMOTE_BROWSER_UPSTREAM| remote and fetch the $BASE_BRANCH
+if git remote get-url $REMOTE_BROWSER_UPSTREAM >/dev/null; then
+  echo "-- setting |$REMOTE_BROWSER_UPSTREAM| remote url to $REMOTE_URL"
+  git remote set-url $REMOTE_BROWSER_UPSTREAM $REMOTE_URL
+else
+  echo "-- adding |$REMOTE_BROWSER_UPSTREAM| remote to $REMOTE_URL"
+  git remote add $REMOTE_BROWSER_UPSTREAM $REMOTE_URL
+fi
+git fetch $REMOTE_BROWSER_UPSTREAM $BASE_BRANCH
+
+# Check if we have the $BASE_REVISION commit in GIT
+if ! git cat-file -e $BASE_REVISION^{commit}; then
+  echo "ERROR: $FRIENDLY_CHECKOUT_PATH/ does not include the BASE_REVISION (@$BASE_REVISION). Wrong revision number?"
+  exit 1
+else
+  echo "-- checking $FRIENDLY_CHECKOUT_PATH repo has BASE_REVISION (@$BASE_REVISION) commit - OK"
+fi
+
+# Check out the $BASE_REVISION
+git checkout $BASE_REVISION
+
+# Create a playwright-build branch and apply all the patches to it.
+if git show-ref --verify --quiet refs/heads/playwright-build; then
+  git branch -D playwright-build
+fi
+git checkout -b playwright-build
+echo "-- applying all patches"
+git am ../patches/*
+
+echo
+echo
+echo "DONE. Browser is ready to be built."
diff --git a/browser_patches/tools/check_cdn.sh b/browser_patches/tools/check_cdn.sh
index e50c4ff404..223c3aab7f 100755
--- a/browser_patches/tools/check_cdn.sh
+++ b/browser_patches/tools/check_cdn.sh
@@ -17,17 +17,17 @@ ARCHIVES=(
   "$HOST/firefox/%s/firefox-linux.zip"
   "$HOST/firefox/%s/firefox-win.zip"
   "$HOST/webkit/%s/minibrowser-linux.zip"
-  "$HOST/webkit/%s/minibrowser-mac10.14.zip"
-  "$HOST/webkit/%s/minibrowser-mac10.15.zip"
+  "$HOST/webkit/%s/minibrowser-mac-10.14.zip"
+  "$HOST/webkit/%s/minibrowser-mac-10.15.zip"
 )
 
 ALIASES=(
   "FF-MAC"
   "FF-LINUX"
   "FF-WIN"
+  "WK-LINUX"
   "WK-MAC-10.14"
   "WK-MAC-10.15"
-  "WK-LINUX"
 )
 COLUMN="%-15s"
 
diff --git a/browser_patches/webkit/BASE_REVISION b/browser_patches/webkit/BASE_REVISION
deleted file mode 100644
index 7b297e2fcc..0000000000
--- a/browser_patches/webkit/BASE_REVISION
+++ /dev/null
@@ -1 +0,0 @@
-734d4fc1b6da79b72e234e4a50435f25dd90d769
diff --git a/browser_patches/webkit/UPSTREAM_CONFIG.sh b/browser_patches/webkit/UPSTREAM_CONFIG.sh
new file mode 100644
index 0000000000..2555176190
--- /dev/null
+++ b/browser_patches/webkit/UPSTREAM_CONFIG.sh
@@ -0,0 +1,3 @@
+REMOTE_URL="https://github.com/webkit/webkit"
+BASE_BRANCH="master"
+BASE_REVISION="734d4fc1b6da79b72e234e4a50435f25dd90d769"
diff --git a/browser_patches/webkit/build.sh b/browser_patches/webkit/build.sh
index 2315846292..571d8da1fa 100755
--- a/browser_patches/webkit/build.sh
+++ b/browser_patches/webkit/build.sh
@@ -6,11 +6,13 @@ trap "cd $(pwd -P)" EXIT
 cd "$(dirname $0)"
 cd "checkout"
 
-if ! [[ $(git rev-parse --abbrev-ref HEAD) == "pwdev" ]]; then
-  echo "ERROR: Cannot build any branch other than PWDEV"
+BUILD_BRANCH="playwright-build"
+
+if ! [[ $(git rev-parse --abbrev-ref HEAD) == "$BUILD_BRANCH" ]]; then
+  echo "ERROR: Cannot build any branch other than $BUILD_BRANCH"
   exit 1;
 else
-  echo "-- checking git branch is PWDEV - OK"
+  echo "-- checking git branch is $BUILD_BRANCH - OK"
 fi
 
 if [[ "$(uname)" == "Darwin" ]]; then