diff --git a/projects/firefox-langpacks/config b/projects/firefox-langpacks/config
index 17a707a5a4784a5b76b33968623a3445aa83b9ea..34d6fad1b5b8301eea2def115afca441ee915734 100644
--- a/projects/firefox-langpacks/config
+++ b/projects/firefox-langpacks/config
@@ -4,7 +4,7 @@ filename: '[% project %]-[% c("version") %]-[% c("var/osname") %]-[% c("var/buil
 
 var:
   ff_version: '[% pc("firefox", "var/firefox_version") %]'
-  ff_build: build2
+  ff_build: build1
   input_filename: 'dl-langpack-[% c("var/ff_arch") %]-[% c("version") %]'
 
 targets:
diff --git a/projects/firefox/config b/projects/firefox/config
index 00d45f324929f5b3b8ba41d9b1822392f96128e9..e9df89509e5e9504671e3fcca19acba787baf055 100644
--- a/projects/firefox/config
+++ b/projects/firefox/config
@@ -8,7 +8,7 @@ git_submodule: 1
 gpg_keyring: torbutton.gpg
 
 var:
-  firefox_platform_version: 78.7.0
+  firefox_platform_version: 78.7.1
   firefox_version: '[% c("var/firefox_platform_version") %]esr'
   torbrowser_branch: 10.5
   branding_directory: 'browser/branding/alpha'
diff --git a/projects/tor-browser/Bundle-Data/Docs/ChangeLog.txt b/projects/tor-browser/Bundle-Data/Docs/ChangeLog.txt
index f1bb8c43f6d73cfaac9bb210fed388fb6c1972c4..12dd037e0bfe51304bf3a9d52dc397a08d37d980 100644
--- a/projects/tor-browser/Bundle-Data/Docs/ChangeLog.txt
+++ b/projects/tor-browser/Bundle-Data/Docs/ChangeLog.txt
@@ -1,3 +1,7 @@
+Tor Browser 10.5a10 -- February 7 2021
+ * Windows
+   * Update Firefox to 78.7.1esr
+
 Tor Browser 10.5a9 -- February 5 2021
  * Android
    * Update Fenix to 86.0.0-beta.2
diff --git a/rbm.conf b/rbm.conf
index a027f7cab264a86be5ff510852bfcb6a594ca3f6..76ab74b84d2d704e08c968cbc7aa9e5bbbfb4e66 100644
--- a/rbm.conf
+++ b/rbm.conf
@@ -24,10 +24,10 @@ buildconf:
   git_signtag_opt: '-s'
 
 var:
-  torbrowser_version: '10.5a9'
+  torbrowser_version: '10.5a10'
   torbrowser_build: 'build1'
   torbrowser_incremental_from:
-    - 10.5a7
+    - 10.5a8
   project_name: tor-browser
   multi_lingual: 0
   build_mar: 1