bug-fix: exclude all whitespaces except space in file name

src/utils/vutils.cpp

@@ -46,7 +46,7 @@ const QString VUtils::c_imageLinkRegExp = QString("\\!\\[([^\\]]*)\\]\\(([^\\)\"
 
 const QString VUtils::c_imageTitleRegExp = QString("[\\w\\(\\)@#%\\*\\-\\+=\\?<>\\,\\.\\s]*");
 
-const QString VUtils::c_fileNameRegExp = QString("[^\\\\/:\\*\\?\"<>\\|]*");
+const QString VUtils::c_fileNameRegExp = QString("(?:[^\\\\/:\\*\\?\"<>\\|\\s]| )*");
 
 const QString VUtils::c_fencedCodeBlockStartRegExp = QString("^(\\s*)```([^`\\s]*)\\s*[^`]*$");
 

src/utils/vutils.h

@@ -367,7 +367,7 @@ public:
     static const QString c_imageTitleRegExp;
 
     // Regular expression for file/directory name.
-    // Forbidden char: \/:*?"<>|
+    // Forbidden char: \/:*?"<>| and whitespaces except space.
     static const QString c_fileNameRegExp;
 
     // Regular expression for fenced code block.