Index: gc_lang/fr/config.ini
==================================================================
--- gc_lang/fr/config.ini
+++ gc_lang/fr/config.ini
@@ -30,11 +30,11 @@
 # Firefox
 fx_identifier = French-GC@grammalecte.net
 fx_name = Grammalecte [fr]
 
 fx_standard_path = C:\Program Files\Mozilla Firefox\firefox.exe
-fx_beta_path = C:\Program Files\Mozilla Firefox Beta\firefox.exe
+fx_dev_path = C:\Program Files\Firefox Developer Edition\firefox.exe
 fx_nightly_path = C:\Program Files (x86)\Nightly\firefox.exe
 
 
 # Thunderbird
 tb_identifier = French-GC-TB@grammalecte.net

Index: make.py
==================================================================
--- make.py
+++ make.py
@@ -348,11 +348,11 @@
                         tests.perf(sVersion, hDst)
 
             # Firefox
             if xArgs.firefox:
                 with helpers.cd("_build/xpi/"+sLang):
-                    os.system("jpm run -b nightly")
+                    os.system('jpm run -b "' + dVars['fx_dev_path'] + '"')
 
             if xArgs.web_ext:
                 with helpers.cd("_build/webext/"+sLang):
                     os.system(r'web-ext run --firefox="' + dVars['fx_nightly_path'] + '" --browser-console')