diff --git a/docs/doxygen/Doxyfile.in b/docs/doxygen/Doxyfile.in
index a50a6801..33bb2566 100644
--- a/docs/doxygen/Doxyfile.in
+++ b/docs/doxygen/Doxyfile.in
@@ -1312,7 +1312,7 @@ HTML_FOOTER            =
 # obsolete.
 # This tag requires that the tag GENERATE_HTML is set to YES.
 
-HTML_STYLESHEET        = "doxygen-awesome-css/doxygen-awesome.css"
+HTML_STYLESHEET        = 
 
 # The HTML_EXTRA_STYLESHEET tag can be used to specify additional user-defined
 # cascading style sheets that are included after the standard style sheets
@@ -1330,7 +1330,7 @@ HTML_STYLESHEET        = "doxygen-awesome-css/doxygen-awesome.css"
 # documentation.
 # This tag requires that the tag GENERATE_HTML is set to YES.
 
-HTML_EXTRA_STYLESHEET  = "doxygen-awesome-css/doxygen-awesome.css"
+HTML_EXTRA_STYLESHEET  = doxygen-awesome-css/doxygen-awesome.css
 
 
 # The HTML_EXTRA_FILES tag can be used to specify one or more extra images or
@@ -2838,9 +2838,9 @@ TEMPLATE_RELATIONS= YES
 DOT_GRAPH_MAX_NODES=100 
 MAX_DOT_GRAPH_DEPTH= 0 
 DOT_TRANSPARENT= YES 
-DISABLE_INDEX= NO
-FULL_SIDEBAR= NO
-GENERATE_TREEVIEW= YES
-HTML_EXTRA_STYLESHEET= doxygen-awesome-css/doxygen-awesome.css \
-                       doxygen-awesome-css/doxygen-awesome-sidebar-only.css
-HTML_COLORSTYLE= LIGHT
\ No newline at end of file
+GENERATE_TREEVIEW      = YES # required!
+DISABLE_INDEX          = NO
+FULL_SIDEBAR           = NO
+HTML_EXTRA_STYLESHEET  = doxygen-awesome-css/doxygen-awesome.css \
+                        doxygen-awesome-css/doxygen-awesome-sidebar-only.css
+HTML_COLORSTYLE        = LIGHT # required with Doxygen >= 1.9.5
\ No newline at end of file