Thanks @rabelux! Is this PR ready for review?

Sure, if you think what I did could work? 😄

@rabelux
Add translation possibility for missing buttons pt2

Translation Spanish ES (Translations.config)

<UI_FontFamily>Segoe UI</UI_FontFamily>
<APP_START>QuickLook está funcionando en segundo plano.</APP_START>
<APP_SECOND>QuickLook ya está funcionando en segundo plano</APP_SECOND>
<APP_SECOND_TEXT>QuickLook permite la previsualización rápida de ciertos tipos de archivos pulsando la barra espaciadora mientras este está resaltado.</APP_SECOND_TEXT>
<APP_PATH_NOT_WRITABLE>No se puede escribir en la ruta "{0}". Por favor, compruebe si tiene suficientes permisos.</APP_PATH_NOT_WRITABLE>
<MW_StayTop>Siempre Encima</MW_StayTop>
<MW_PreventClosing>Evitar Cierre</MW_PreventClosing>
<MW_BrowseFolder>Explorar {0}</MW_BrowseFolder>
<MW_Open>Abrir {0}</MW_Open>
<MW_OpenWith>Abrir con {0}</MW_OpenWith>
<MW_OpenWithMenu>Abrir Con Menu</MW_OpenWithMenu>
<MW_Run>Iniciar {0}</MW_Run>
<MW_Share>Compartir</MW_Share>
<Icon_RunAtStartup>Iniciar con el &sistema</Icon_RunAtStartup>
<Icon_ToolTip>QuickLook v{0}</Icon_ToolTip>
<Icon_CheckUpdate>Buscar &Actualizaciones...</Icon_CheckUpdate>
<Icon_GetPlugin>Buscar nuevos &Plugins...</Icon_GetPlugin>
<Icon_Quit>&Salir</Icon_Quit>
<Update_NoUpdate>Está usando la última versión.</Update_NoUpdate>
<Update_Found>QuickLook {0} está disponible. Haga clic aquí para abrir la página de descarga.</Update_Found>
<Update_Error>Ocurrió un error al buscar actualizaciones: {0}</Update_Error>
<InfoPanel_LastModified>Última modificación el {0}</InfoPanel_LastModified>
<InfoPanel_DriveSize>Capacidad {0}, {1} disponible</InfoPanel_DriveSize>
<InfoPanel_Folder>{0} carpeta</InfoPanel_Folder>
<InfoPanel_Folders>{0} carpetas</InfoPanel_Folders>
<InfoPanel_File>{0} archivo</InfoPanel_File>
<InfoPanel_Files>{0} archivos</InfoPanel_Files>
<InfoPanel_FolderAndFile>({0} y {1})</InfoPanel_FolderAndFile>

@xupefei does my approach look good to you? Can this be merged?

Thanks for the PR!
We don't need to load translations on every preview, but once during window initialization, i.e., somewhere here: https://github.com/QL-Win/QuickLook/blob/master/QuickLook/ViewerWindow.xaml.cs#L99. Just make sure they come after InitializeComponent().

Hey @rabelux, any updates on this PR? After you change I want to contribute Chinese and Japanese translations to this PR 😀

Hi @xupefei, I'm really short on time at the moment and as I'm not really having a clue what I'm doing here, could you finish what I started? I think I allowed edits by maintainers for this PR.