When You create a DataFormWebPart on a web part page in SharePoint Designer and edit the page in Normal Mode by clicking the Edit file link in the page information Customization section. Then you switch to Advanced Mode using the Advanced Mode ribbon button. After doing so you notice that extra white spaces and false characters such as are unexpectedly added to the XSLT. Subsequent page editing from the Advanced Mode button inserts additional white spaces into the DataFormWebPart XSLT. These extra spaces and characters remain embedded if you save the page.
When you switch editing to Advanced Mode using the Edit file link in the page information Customization section, SharePoint Designer adds white spaces and false characters to the XSLT. This is a known issue with SharePoint Designer 2013.
Start page editing by clicking the Edit File button dropdown menu on the ribbon and selecting Edit File in Advanced Mode in the dropdown list as this issue does not happen when you Edit in Advanced Mode
Post By: Vikram Kartik Jindal