title: NSIS can't use a macro when using Modern UI
body: <p>I have a file <code>section-db.nsh</code> containing:</p>
  
  <pre><code>!macro uninstall_myrian
      Delete $APPDATA\Intrasense\settings\admin.txt
      Delete $APPDATA\Intrasense\settings\user.txt    
  !macroend
  </code></pre>
  
  <p>and <code>test.nsi</code> with</p>
  
  <pre><code>!include "MUI2.nsh"
  !include "section-db.nsh"
  
  Name "Software"
  OutFile "installer.exe"
  
  !insertmacro MUI_PAGE_WELCOME
  !insertmacro MUI_PAGE_INSTFILES
  
  Section hello
  SectionEnd
  </code></pre>
  
  <p>Should compile correctly, right? well no:</p>
  
  <blockquote>
  <pre><code>!include: "section-db.nsh"
  !macro: macro named "uninstall_myrian" already found!
  !include: error in script: "section-db.nsh" on line 2
  Error in script "Y:\prog\scripts\installer-script\test.nsi" on line 2 -- aborting creation process
  </code></pre>
  </blockquote>
  
  <p>If I comment the MUI2.nsh include, it compiles correctly. </p>
  
  <p>If I rename the macro to <code>myrian_uninst</code>, it compiles correctly.</p>
  
  <p>What's the problem?</p>