Upgrade to QCAD 3.21.2.3, with changes:

3.21.2 (2018/07/09):

    Modify:
        Restructure menu into submenus
    Layer list, block list:
        Improve sorting for international characters (�, �, etc.)
    Bug fixes:
        FS#1776 - Edit > Application Preferences: Tool Settings: cannot configure shortcuts
        FS#1777 - Crash when pasting / importing drawing with missing image
        FS#1778 - Draw > Point > Single Point: Exception

3.21.1 (2018/06/29):

    Draw > Circle > 3 Tangents:
        Allow all tangents to be segments of same polyline
    Bug fixes:
        FS#1180 - dxflib cannot open files with international characters in path or file name
        FS#1773 - File > PDF Export / SVG Export / Bitmap Export: file name suggestion in file dialog is drawing file
        FS#1775 - Viewports: images sometimes not clipped at viewport edge

3.21.0 (2018/06/26):

    Dimension:
        Add option to flip first / second arrow
        Add reference points to flip arrows using mouse click
        Angular:
            Add option "Use maximum angle" to angle dimension tool for angles > 180�
            Add support for 3 point angle dimensions (required for angle dimensions > 180�)
    Polylines:
        Add reference points at middle of line segments to move line segments
    Edit > Application Preferences:
        Keyboard > Enable keyboard navigation in list widgets:
            Enable / disable keyboard navigation in list widgets (up/down, type first letters)
        Layer > Add Layer:
            Add separate default attributes for layer 0
        Graphics View > Navigation:
            Add "Middle mouse button zoom factor"
            Add "Panning threshold"
    Draw > Image:
        Transparent live preview when inserting / modifying images
        Scale image using drag and drop on corners
            Keep aspect ratio using Shift
    Improve display of reference points
        Always display in front of highlighted entities
        Add border around reference points
    Zoom in by clicking middle mouse button (out using Shift+middle mouse button)
    View > Property Editor:
        Add support for requestible (slow) properties
    Bug fixes:
        FS#1741 - Property Editor: titles of block attributes with _ cut off
        FS#1742 - File > Print: printed point size depends on zoom level
        FS#1743 - Draw > Text: Wrong bounding box for text with empty supper or subscript
        FS#1745 - File > Bitmap Export: thick lines exported thin
        FS#1753 - View > Property Editor: entity types in property editor not translated
        FS#1756 - Polyline area wrong if polyline contains arc segments
        FS#1757 - Modify > Auto Trim: on polyline, followed by undo yields corrupt / invisible polyline
        FS#1758 - Draw > Polyline > Create from Selected Entities: crash for geometrically closed polylines
        FS#1766 - Edit > Application Preferences: Tool Settings: cannot add menus to Tool Matrix
        FS#1768 - Draw > Polyline > Create From Segments: segments deleted even if no polyline can be added

3.20.1 (2018/04/13):

    Bug fixes:
        FS#1736 - Draw > Image: broken
        FS#1737 - Block > Attributes > Define Block Attribute: broken
        FS#1738 - File > Print / PDF Export: shortcut broken in print preview

3.20.0 (2018/04/12):

    QCAD API:
        Add support for property attributes for custom properties
            Read-only
            Undeletable
            Invisible
            Choices (combo box)
        Allow translation of custom property labels
    Translations:
        Add support for complex plural forms in certain languages (singular, paucal, plural)
        Complete Polish translation
    Deployment:
        Bundle script files and resources as plugin (speed up installation, updates and start up)
    Bug fixes:
        FS#1686 - File > Print: Line scale in Viewport wrong if Model_Space not 1:1
        FS#1677 - Dimension: Scale option grayed out in model space
        FS#1696 - Modify > Isometric Projection > Cylindrical: exception
        FS#1695 - Context menu: editing tools not working in paper space
        FS#1703 - File > Bitmap Export: Monochrome with black background broken
        FS#1704 - Wrong labels for information area buttons
        FS#1712 - dwg2pdf: auto fit fails for blocks
        FS#1720 - Modify > Auto Trim: fails for Rays and Infinite Lines
        FS#1734 - Draw > Text: Color changes for CAD font texts ignored

3.19.2 (2017/12/20):

    Modify > Stretch:
        Only stretch selected entities if there is a selection
    File > Bitmap Export:
        Add option for transparent background
        Add option to only export bounding box of selection
    Bug fixes:
        FS#1659 - File > Print Preview: does not always open / close properly
        FS#1664 - Block > Insert Block: attribute color not synced with attribute definition color
        FS#1665 - Edit > Drawing / Application Preferences > Point Display: second last button has no effect
        FS#1669 - Edit > Application Preferences > Defaults for New Drawings > Dimension Settings: math expressions
        FS#1670 - Layout Blocks are not using print settings from Application Preferences
        FS#1671 - Block > Add Layout Block: fails if layout with same name was deleted before
        FS#1682 - Draw > Text: line spacing factor < 0.25 or > 4.0 causes entity not being saved


(plunky)