1. Select block to place into drawing
2. Change x-scale to 1/3, observe grayed out y-scale shows (.333)
3. Click chain to unlink x & y scales
4. Change y-scale to 1/2
5. Click chain again to relink x & y scales and y-scale box grays out but 1/2 remains
6. Block is placed using x = 1/3 and y = 1/2 even though the chain shows x & y linked and 1/2 grayed out

See:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=4048

Application preference to show / hide scrollbars has no effect (scrollbars always shown).

Block references to blocks with an origin other than 0,0 are not selectable.

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=89&t=4063

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=31&t=4068

Editing redundant properties in the property editor has no effect (e.g. length of line, area of circle, ...)

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=76&t=4019

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=4078

The very first entity drawn / loaded does not preserve its drawing order when copied / pasted.

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=89&t=4089&view=unread#unread

Texts (if rendered as text not paths) and images are rendered in the background if they are inside a block.

- Create block with text or bitmap in front of other entities
- Insert block
- Text and bitmaps are rendered behind entities

Hatch boundaries containing arcs with large radii are rendered imprecisely.
See also:
http://www.qcad.org/rsforum/viewtopic.php?f=89&t=4139

Panning with two-finger up/down left/right movement does not work with Qt 5 based builds.

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=4148

If the drawing unit is set to ‘feet’ and the dimension format is ‘architectural’ or ‘engineering’, the drawing unit should be implicitly regarded as inch for the purpose of calculating dimension values. Since QCAD uses the drawing unit, the dimension values are off by a factor of 12 when importing drawings from other products.

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=89&t=4235&start=15

QCAD3.ini may contain invalid positions for the main application windows, e.g.
[Appearance]
Position.X=-32000
Position.Y=-32000

This leads to an invisible main window after starting QCAD under Windows systems.

Modify > Trim
Choose line as limiting entity
Choose spline as entity to trim
The part of the spline that was clicked should remain but is trimmed instead

See also:
http://www.ribbonsoft.com/rsforum/viewtopic.php?f=89&t=4235&start=15

Dots in line patterns along polylines with property “Polyline Pattern” set to “Yes” are rendered as horizontal lines.
See also:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=4262

If text style has a text width (x scale) that is not 1, the property x scale from the text style is applied to all texts of that style.
See also:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=4266

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=4269

Prints under Windows are offset by the default printer margins.

This is caused by QTBUG-5363, https://bugreports.qt.io/browse/QTBUG-5363

Library items created from existing drawings should have the same unit as the drawing. Currently, the unit of newly created library items is ‘None’.

Vertical alignment “base” (not supported for MText) is saved as “top”. Using “bottom” to replace “base” would be more appropriate.

Modify > Lengthen with positive values can shorten the polyline in some cases.
See also:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=4303

Context menu does not show an entry to “Delete Node” for the first node of a polyline.

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=32&t=4310

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=4318

- Create some points
- Modify > Clip to Rectangle
- Make sure some points are inside rectangle

→ Exception

Drag and drop requires two clicks with auto snap if grid snap and free snap are disabled for auto snap.
- Edit > Application Preferences > Snap > Auto Snap: disable grid and free
- Drag an entity and try to position it
- First click does nothing, second click positions entity

- Create four arc segments representing a full circle
- Create polyline from segments

Empty polyline is created (caused by simplification).

Draw > Circle > 2 Tangents and Radius
Choose two arcs or two circles as tangential entities.

Exploding splines creates more segments than necessary in some cases with very large tolerances.
The number of segments created should be the number of bezier spline segments times two.

- Select a block in the block list.
- Toggle the visibility of another block or add a block, etc.
- Selected block changes

Not all intersections points between ellipses and circles or other ellipses are found.
This is due to too tight tolerances.

See:
http://www.qcad.org/rsforum/viewtopic.php?f=76&t=4574

See also:
http://www.qcad.org/rsforum/viewtopic.php?f=33&t=4583

Create block reference with attribute
Copy block reference and attribute
Paste

The copied attribute is now associated with the first block reference instead of the second.

Occurs when breaking out segment from closed polyline with more than two intersecting entities.

This also affects the hatch from segments tool when used with closed polylines.

Example:
https://raw.githubusercontent.com/qcad/qcad/master/scripts/Modify/BreakOut/Tests/data/closed_polyline.dxf

Rulers show only whole numbers.

- Create spline from fit points
- Rotate spline
- Spline shape changes due to erroneous start/end tangents

Similar problem when reversing spline from fit points.

Offset curve not trimmed / clipped correctly.

Offset distance: 2.5

- Draw circle inside other circle
- Draw > Hatch > Hatch from Segments
- Click both circles
- Right-click

@ sign cannot be entered into command line on German keyboards on which Alt-Q has to be pressed to enter @.

This is a Qt/Linux bug which interprets Alt-Q as part of a shortcut starting with Q.

Workaround: change shortcut of Reset tool from QQ to something else, not starting with Q.

Draw > Line > Parallel
- switch type to Line, XLine or Ray
- switch back to Auto
- Parallel is always line segment

Files imported from other CAD applications might contain blocks that are mirrored if the block reference uses an inverted extrusion direction.

See also:
https://www.qcad.org/rsforum/viewtopic.php?f=32&t=4776

See also:
https://www.qcad.org/rsforum/viewtopic.php?f=32&t=4774

Zero length lines are not shown in QCAD. For best compatibility these should be shown as dots.

Font substitutions broken for many cases.
Font “Standard” can never be substituted.

Qt menu heuristic causes Edit > Drawing Preferences to disappear with French locale under macOS.

Edit > Application Preferences and Help > About are moved to erroneous locations as well.