Known issues

Open bugs and limitations in V1.0, with workarounds where available. The authoritative list is ISSUES.md in the source repo.

Table of contents

• ISSUE-004 — <label> background-color rgba alpha ignored in runtime
  • Symptom
  • Workaround
  • Status
• ISSUE-005 — PreviewCount badges not emitted in runtime
  • Symptom
  • Workaround
  • Status
• Limitations (not bugs)
  • .User.scss not visible in Test in Play
  • Test in Play has no scene auto-restore
  • One Play session at a time
  • flex-grow / flex-shrink / flex-basis not honored by canvas
  • align-self not honored
  • display: grid is forbidden
  • Multi-document workspace doesn’t exist
• Closed issues (historical)
• Reporting new issues
• See also

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ISSUE-004 — <label> background-color rgba alpha ignored in runtime

Severity: major · Status: investigating

Symptom

Text elements (which the generator emits as <label>) with background-color: rgba(r,g,b,a) where a < 1 render the background as fully opaque in Test in Play and the runtime preview. The alpha is ignored.

Canvas (paint-based) renders correctly — rgba(34, 197, 94, 0.12) appears as a very faint green over a dark sidebar.

In runtime: the same element appears as solid/saturated green, as if alpha = 1.0.

Confirmed reproduction: quest_log.sui samples (Drink from the River / Light a Campfire) and loot_pickup.sui — every <label> with rgba alpha below ~0.5 renders solid in runtime.

Workaround

Wrap the Text in a Panel and put the background on the Panel:

Before (broken in runtime):

Text (Background: rgba(34, 197, 94, 0.12), Text: "Quest complete")

After (works):

Panel (Background: rgba(34, 197, 94, 0.12))
└── Text (Text: "Quest complete")

The Panel emits as <div> which respects rgba alpha correctly. The Text inside has a transparent background.

Status

Filed under investigation. The root cause is likely a special handling of <label> background in the Sandbox.UI parser. We’re choosing between two fixes:

1. Make the generator emit <div> when a Text element has a background-color set.
2. Wrap label in a div automatically: <div class="..."><label>text</label></div>.

Either way: a future SUI version will handle this transparently.

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ISSUE-005 — PreviewCount badges not emitted in runtime

Severity: minor · Status: open

Symptom

InventorySlot and ItemIcon elements have a PreviewCount prop (e.g. "20", "3"). The canvas draws this count as an overlay in the slot’s bottom-right corner.

In runtime Test in Play, the count doesn’t appear. The Razor generator doesn’t emit the <label> child with the count text.

Result: canvas shows “20” on top of a berry stack; runtime shows only the icon.

Workaround

For previews / mockups, this is cosmetic only. For real gameplay UIs, you’ll be driving the count from your C# code anyway (binding the count text to ItemStack.Count or similar), so the static PreviewCount isn’t load-bearing.

If you need the badge visible in Test in Play for screenshot purposes, add a manual Text child:

InventorySlot
└── ItemIcon
└── Text (Anchor: BottomRight, Text: "20", FontWeight: Bold, Color: white)

Status

Tracked. Future fix: generator adds an automatic count <label> when PreviewCount > 0, plus matching SCSS for absolute positioning.

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Limitations (not bugs)

These are deliberate V1 scope limits, not bugs to be fixed:

.User.scss not visible in Test in Play

Test in Play runs the generator in Preview mode which skips the @import "<Name>.User.scss". The sidecar doesn’t exist at the preview cache path.

Impact: hovers, animations, shadows in .User.scss only appear after a real Compile + Play.

Why: importing a non-existent file silently breaks SCSS compilation at runtime. The fix is to emit the import only in Final mode.

Test in Play has no scene auto-restore

After clicking Stop, you remain on preview_stage.scene. There’s no API in s&box for the addon to safely restore your previous scene.

Workaround: open your original scene manually from the Asset Browser.

One Play session at a time

You can’t run Test in Play on a .sui while another play session is active. Stop the existing one first.

Why: s&box doesn’t support nested play sessions.

flex-grow / flex-shrink / flex-basis not honored by canvas

The canvas’s flex solver doesn’t implement flex-grow. Children always use their intrinsic size. The runtime CSS engine DOES honor flex-grow.

Impact: if you set flex-grow: 1 via .User.scss, canvas and runtime will diverge.

V2: full flex algorithm.

align-self not honored

Children in a flex container inherit the parent’s align-items. Per-child override isn’t exposed in the inspector.

Workaround: override in .User.scss:

MyHud {
  .important-item { align-self: flex-end; }
}

display: grid is forbidden

s&box’s Yoga engine doesn’t support CSS Grid. SUI’s Grid element uses wrapped flex.

Workaround: use the Grid element type — it does what you want.

Multi-document workspace doesn’t exist

One .sui open per window. To work on two HUDs at once, open two SUI Designer windows.

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Closed issues (historical)

The full ISSUES.md in the source repo tracks resolved bugs with their fix history:

• ISSUE-001 — ColorPicker SV box stale on hue change — resolved by replacing the editor’s color picker with a custom SUI implementation (SuiColorPickerPopup).
• ISSUE-002 — Text vertical alignment divergence between canvas and runtime — resolved by introducing SuiTextSizeMode { Auto, Fixed, AutoHeightWrap } and per-mode rendering.
• ISSUE-003 — Editor color picker instability (5 related symptoms) — resolved alongside ISSUE-001 via the custom picker.

See ISSUES.md for the full repro + design discussion that led to each fix.

Reporting new issues

Found a bug not on this list? Open an issue on GitHub with:

1. A repro .sui file (attach or paste contents).
2. Expected vs actual behavior.
3. Whether it shows in canvas, Test in Play, or both.
4. Engine console output if compile-related.

See also

• Test in Play limitations
• User SCSS customization — for things .User.scss lets you sidestep