Do not write an empty default_otf_view_format.

Fixes: #9100.

diff --git a/src/LyXRC.cpp b/src/LyXRC.cpp
index 80b85141d25145e2a3eab443aae6030d480e19b1..c95cacd606636dc868a4af52865eee2b57bf0a63 100644 (file)
--- a/src/LyXRC.cpp
+++ b/src/LyXRC.cpp
@@ -2829,8 +2829,9 @@ void LyXRC::write(ostream & os, bool ignore_system_lyxrc, string const & name) c
                        break;
        }
        case RC_DEFAULT_OTF_VIEW_FORMAT:
-               if (ignore_system_lyxrc ||
-                   default_otf_view_format != system_lyxrc.default_otf_view_format) {
+        if ((ignore_system_lyxrc ||
+            default_otf_view_format != system_lyxrc.default_otf_view_format)
+            && !default_otf_view_format.empty()) {
                        os << "\\default_otf_view_format " << default_otf_view_format << '\n';
                }
                if (tag != RC_LAST)