# G4: Corner component cannot be added to a monoline stroke

**URL:** <https://forum.glyphsapp.com/t/g4-corner-component-cannot-be-added-to-a-monoline-stroke/37286>\
**Category:** Glyphs\
**Created:** [September 16, 2026, 7:03am UTC](https://forum.glyphsapp.com/t/g4-corner-component-cannot-be-added-to-a-monoline-stroke/37286 "2026-09-16T07:03:10Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![tanukizamurai](https://forum.glyphsapp.com/user_avatar/forum.glyphsapp.com/tanukizamurai/32/4661_2.png) [@tanukizamurai](https://forum.glyphsapp.com/u/tanukizamurai)\
**Post date:** [September 16, 2026, 7:03am UTC](https://forum.glyphsapp.com/t/g4-corner-component-cannot-be-added-to-a-monoline-stroke/37286/1 "2026-09-16T07:03:11Z")

</div>

Hi,

I found a difference between Glyphs 3 and Glyphs 4 when adding a corner component to a monoline stroke.

In Glyphs 3, I can add `_corner.stem` to the corner/extra node of the stroke, and the corner component is generated correctly.

![glyphs3-corner-component](https://forum.glyphsapp.com/uploads/default/original/3X/8/c/8c93095eed7e0105e081347c3ab6efc065eee160.gif)

In Glyphs 4, using the same setup and the same corner component, a red circle appears at the target point and the corner component is not generated.

![glyphs4-corner-component](https://forum.glyphsapp.com/uploads/default/original/3X/6/b/6b89e39ab3017c43ad68f5a13c101de20be79ef0.gif)

I can reproduce this in a minimal test font. I tested this in Glyphs 4.1.1 (4108), launched in Disable Plug-ins mode.

I have attached the minimal `.glyphs` source file used for this test.

[corner\_components.glyphs](https://forum.glyphsapp.com/uploads/short-url/alV7agK9gO6wHTZWHMhc5gB0OVb.glyphs) (9.0 KB)

Could you please let me know whether there is a workaround? If not, could this be fixed in Glyphs 4?

Thank you!

---

<div class="post-metadata">

**Author:** ![tanukizamurai](https://forum.glyphsapp.com/user_avatar/forum.glyphsapp.com/tanukizamurai/32/4661_2.png) [@tanukizamurai](https://forum.glyphsapp.com/u/tanukizamurai)\
**Post date:** [October 4, 2026, 7:36am UTC](https://forum.glyphsapp.com/t/g4-corner-component-cannot-be-added-to-a-monoline-stroke/37286/2 "2026-10-04T07:36:38Z")

</div>

An update:

You may already be aware of this, but a similar issue occurs when adding cap components to open stroked paths with pen points in Glyphs 4.2 (4200). Immediately after adding the cap, it sometimes appears only in the preview, but disappears after saving and reopening the file.

Both corner and cap components worked in Glyphs 4 up to and including build 4004. However, I’d prefer to keep using the latest version rather than downgrade solely to work around this issue.

In `I.001` in the attached `corner_components.glyphs`, saving after adding the corner component stores the `_corner.stem` hint without an `origin` entry:

```auto
{
name = _corner.stem;
type = Corner;
}

```

Separate cap tests in 4200 showed the same missing `origin` entry. Setting `originNode` through the scripting API also did not persist after the layer updated.

I also tested build 4004. After reassigning `_corner.stem` in `I.001` through the scripting API, both `originNode` and the attachment reference in the saved file were retained after saving and reopening. The corner also displayed correctly in the Edit view. The saved hint contained:

```auto
{
name = _corner.stem;
origin = (0,1);
stem = 1004;
type = Corner;
}

```

I hope this information helps narrow down any changes in how attachment references are handled.

Thank you for your continued help.