fix(editor): stabilize themes and line numbers for v0.4.19

CHANGELOG.md

@@ -4,6 +4,18 @@ All notable changes to **Neon Vision Editor** are documented in this file.
 
 The format follows *Keep a Changelog*. Versions use semantic versioning with prerelease tags.
 
+## [v0.4.19] - 2026-02-16
+
+### Added
+- Added adaptive theme background normalization so selected themes follow appearance mode (light in Light mode, dark in Dark/System-dark mode) without changing theme identity.
+
+### Improved
+- Improved cross-platform editor readability by enforcing mode-aware base/background contrast for all built-in themes, including Neon Glow.
+
+### Fixed
+- Fixed macOS line-number ruler behavior where line numbers could disappear near end-of-document when scrolling to the bottom.
+- Fixed iOS line-number gutter sync at bottom scroll positions by clamping gutter content offset to valid bounds.
+
 ## [v0.4.18] - 2026-02-15
 
 ### Added

Neon Vision Editor.xcodeproj/project.pbxproj

@@ -358,7 +358,7 @@
 				CODE_SIGNING_ALLOWED = YES;
 				CODE_SIGN_IDENTITY = "Apple Development";
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 234;
+				CURRENT_PROJECT_VERSION = 235;
 				DEAD_CODE_STRIPPING = YES;
 				DEVELOPMENT_TEAM = CS727NF72U;
 				ENABLE_APP_SANDBOX = YES;
@@ -438,7 +438,7 @@
 				CODE_SIGNING_ALLOWED = YES;
 				CODE_SIGN_IDENTITY = "Apple Development";
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 234;
+				CURRENT_PROJECT_VERSION = 235;
 				DEAD_CODE_STRIPPING = YES;
 				DEVELOPMENT_TEAM = CS727NF72U;
 				ENABLE_APP_SANDBOX = YES;

Neon Vision Editor/UI/ContentView+Actions.swift

@@ -398,10 +398,8 @@ extension ContentView {
             if enabled {
                 // Keep toolbar material blended with the titlebar instead of rendering as a separate solid strip.
                 window.toolbarStyle = .unified
-                window.toolbar?.showsBaselineSeparator = false
                 window.styleMask.insert(.fullSizeContentView)
             } else {
-                window.toolbar?.showsBaselineSeparator = true
                 window.styleMask.remove(.fullSizeContentView)
             }
             if #available(macOS 13.0, *) {

Neon Vision Editor/UI/EditorTextView.swift

@@ -2092,6 +2092,7 @@ final class LineNumberedTextViewContainer: UIView {
         lineNumberView.isEditable = false
         lineNumberView.isSelectable = false
         lineNumberView.isScrollEnabled = true
+        lineNumberView.bounces = false
         lineNumberView.isUserInteractionEnabled = false
         lineNumberView.backgroundColor = UIColor.secondarySystemBackground.withAlphaComponent(0.65)
         lineNumberView.textColor = .secondaryLabel
@@ -2132,6 +2133,7 @@ final class LineNumberedTextViewContainer: UIView {
         let numbers = (1...lineCount).map(String.init).joined(separator: "\n")
         lineNumberView.font = UIFont.monospacedDigitSystemFont(ofSize: max(11, fontSize - 1), weight: .regular)
         lineNumberView.text = numbers
+        lineNumberView.layoutIfNeeded()
     }
 }
 
@@ -2532,7 +2534,11 @@ struct CustomTextEditor: UIViewRepresentable {
 
         func syncLineNumberScroll() {
             guard let textView, let lineView = container?.lineNumberView else { return }
-            lineView.contentOffset = CGPoint(x: 0, y: textView.contentOffset.y)
+            let targetY = textView.contentOffset.y + textView.adjustedContentInset.top - lineView.adjustedContentInset.top
+            let minY = -lineView.adjustedContentInset.top
+            let maxY = max(minY, lineView.contentSize.height - lineView.bounds.height + lineView.adjustedContentInset.bottom)
+            let clampedY = min(max(targetY, minY), maxY)
+            lineView.setContentOffset(CGPoint(x: 0, y: clampedY), animated: false)
         }
     }
 }

Neon Vision Editor/UI/LineNumberRulerView.swift

@@ -77,7 +77,7 @@ final class LineNumberRulerView: NSRulerView {
 
         let visibleRectInContainer = visibleRect.offsetBy(dx: -tcOrigin.x, dy: -tcOrigin.y)
         let visibleGlyphRange = lm.glyphRange(forBoundingRect: visibleRectInContainer, in: textContainer)
-        guard visibleGlyphRange.location != NSNotFound, visibleGlyphRange.length > 0 else { return }
+        guard visibleGlyphRange.location != NSNotFound else { return }
 
         var drawnLineStarts = Set<Int>()
         lm.enumerateLineFragments(forGlyphRange: visibleGlyphRange) { [self] _, usedRect, _, glyphRange, _ in
@@ -111,6 +111,21 @@ final class LineNumberRulerView: NSRulerView {
             let drawPoint = NSPoint(x: self.bounds.maxX - size.width - self.inset, y: drawY)
             numberString.draw(at: drawPoint, withAttributes: attributes)
         }
+
+        // Keep the last line number visible near end-of-document/bottom-scroll edge cases
+        // where AppKit can report an empty visible glyph range.
+        if drawnLineStarts.isEmpty, textLength > 0 {
+            let lastLineNumber = fullString.components(separatedBy: .newlines).count
+            let numberString = NSString(string: "\(lastLineNumber)")
+            let attributes: [NSAttributedString.Key: Any] = [
+                .font: font,
+                .foregroundColor: textColor
+            ]
+            let size = numberString.size(withAttributes: attributes)
+            let drawY = max(bounds.minY + 2, bounds.maxY - size.height - 6)
+            let drawPoint = NSPoint(x: bounds.maxX - size.width - inset, y: drawY)
+            numberString.draw(at: drawPoint, withAttributes: attributes)
+        }
     }
 
     private func installObservers(textView: NSTextView) {

Neon Vision Editor/UI/PanelsAndHelpers.swift

@@ -220,12 +220,12 @@ struct WelcomeTourView: View {
     private let pages: [TourPage] = [
         TourPage(
             title: "What’s New in This Release",
-            subtitle: "Major changes since v0.4.17:",
+            subtitle: "Major changes since v0.4.18:",
             bullets: [
-                "Added iOS/macOS regression coverage in the editor refresh path so syntax highlighting remains stable across toolbar/menu and focus transitions.",
-                "Improved editor rendering consistency by preventing view-update color assignments from overriding attributed syntax token colors.",
-                "Fixed iOS issue where opening the toolbar `...` menu could temporarily drop syntax highlighting.",
-                "Fixed macOS issue where moving focus away from the editor/window could temporarily drop syntax highlighting."
+                "Added adaptive theme background normalization so selected themes follow appearance mode (light in Light mode, dark in Dark/System-dark mode) without changing theme identity.",
+                "Improved cross-platform editor readability by enforcing mode-aware base/background contrast for all built-in themes, including Neon Glow.",
+                "Fixed macOS line-number ruler behavior where line numbers could disappear near end-of-document when scrolling to the bottom.",
+                "Fixed iOS line-number gutter sync at bottom scroll positions by clamping gutter content offset to valid bounds."
             ],
             iconName: "sparkles.rectangle.stack",
             colors: [Color(red: 0.40, green: 0.28, blue: 0.90), Color(red: 0.96, green: 0.46, blue: 0.55)],

Neon Vision Editor/UI/ThemeSettings.swift

@@ -44,6 +44,69 @@ struct ThemePaletteColors {
     let builtin: Color
 }
 
+private struct RGBColorComponents {
+    let red: Double
+    let green: Double
+    let blue: Double
+}
+
+private func colorComponents(_ color: Color) -> RGBColorComponents? {
+#if os(macOS)
+    let platform = PlatformColor(color)
+    guard let srgb = platform.usingColorSpace(.sRGB) else { return nil }
+    return RGBColorComponents(
+        red: Double(srgb.redComponent),
+        green: Double(srgb.greenComponent),
+        blue: Double(srgb.blueComponent)
+    )
+#else
+    let platform = PlatformColor(color)
+    var red: CGFloat = 0
+    var green: CGFloat = 0
+    var blue: CGFloat = 0
+    var alpha: CGFloat = 0
+    guard platform.getRed(&red, green: &green, blue: &blue, alpha: &alpha) else { return nil }
+    return RGBColorComponents(red: Double(red), green: Double(green), blue: Double(blue))
+#endif
+}
+
+private func relativeLuminance(_ components: RGBColorComponents) -> Double {
+    (0.2126 * components.red) + (0.7152 * components.green) + (0.0722 * components.blue)
+}
+
+private func blend(_ source: Color, with target: Color, amount: Double) -> Color {
+    guard let sourceComponents = colorComponents(source), let targetComponents = colorComponents(target) else {
+        return source
+    }
+    let clamped = min(1.0, max(0.0, amount))
+    return Color(
+        red: sourceComponents.red + ((targetComponents.red - sourceComponents.red) * clamped),
+        green: sourceComponents.green + ((targetComponents.green - sourceComponents.green) * clamped),
+        blue: sourceComponents.blue + ((targetComponents.blue - sourceComponents.blue) * clamped)
+    )
+}
+
+private func modeAdjustedEditorBackground(_ background: Color, colorScheme: ColorScheme) -> Color {
+    guard let components = colorComponents(background) else { return background }
+    let luminance = relativeLuminance(components)
+
+    if colorScheme == .light {
+        // Keep all themes readable in light/system-light by lifting dark palettes.
+        if luminance >= 0.78 { return background }
+        let targetLuminance = 0.96
+        let normalized = (targetLuminance - luminance) / max(0.0001, 1.0 - luminance)
+        let mixAmount = min(0.95, max(0.70, normalized))
+        return blend(background, with: .white, amount: mixAmount)
+    }
+
+    // Keep all themes readable in dark/system-dark by lowering bright palettes.
+    if luminance <= 0.28 { return background }
+    let targetLuminance = 0.14
+    let normalized = (luminance - targetLuminance) / max(0.0001, luminance)
+    let mixAmount = min(0.90, max(0.55, normalized))
+    return blend(background, with: .black, amount: mixAmount)
+}
+
 ///MARK: Theme Name Canonicalization
 
 // Canonical theme names shown in settings and used for palette lookup.
@@ -322,7 +385,7 @@ func currentEditorTheme(colorScheme: ColorScheme) -> EditorTheme {
 
     return EditorTheme(
         text: baseTextColor,
-        background: palette.background,
+        background: modeAdjustedEditorBackground(palette.background, colorScheme: colorScheme),
         cursor: palette.cursor,
         selection: palette.selection,
         syntax: syntax

README.md

@@ -17,7 +17,7 @@
 </p>
 
 > Status: **active release**  
-> Latest release: **v0.4.18**
+> Latest release: **v0.4.19**
 > Platform target: **macOS 26 (Tahoe)** compatible with **macOS Sequoia**
 > Apple Silicon: tested / Intel: not tested
 
@@ -25,7 +25,7 @@
 
 Prebuilt binaries are available on [GitHub Releases](https://github.com/h3pdesign/Neon-Vision-Editor/releases).
 
-- Latest release: **v0.4.18**
+- Latest release: **v0.4.19**
 - Apple AppStore [On the AppStore](https://apps.apple.com/de/app/neon-vision-editor/id6758950965)
 - TestFlight beta: [Join here](https://testflight.apple.com/join/YWB2fGAP)
 - Architecture: Apple Silicon (Intel not tested)
@@ -123,6 +123,13 @@ If macOS blocks first launch:
 
 ## Changelog
 
+### v0.4.19 (summary)
+
+- Added adaptive theme background normalization so selected themes follow appearance mode (light in Light mode, dark in Dark/System-dark mode) without changing theme identity.
+- Improved cross-platform editor readability by enforcing mode-aware base/background contrast for all built-in themes, including Neon Glow.
+- Fixed macOS line-number ruler behavior where line numbers could disappear near end-of-document when scrolling to the bottom.
+- Fixed iOS line-number gutter sync at bottom scroll positions by clamping gutter content offset to valid bounds.
+
 ### v0.4.18 (summary)
 
 - Added iOS/macOS regression coverage in the editor refresh path so syntax highlighting remains stable across toolbar/menu and focus transitions.
@@ -136,14 +143,6 @@ If macOS blocks first launch:
 - Improved syntax-highlighting stability during appearance/translucency transitions by forcing an immediate refresh instead of waiting for unrelated edits.
 - Fixed a macOS editor bug where toggling translucent window mode could temporarily hide syntax highlighting until another action (for example changing font size) forced a rehighlight.
 
-### v0.4.16 (summary)
-
-- Added a release-doc synchronization gate to `release_all.sh` via `prepare_release_docs.py --check` so releases fail fast when docs are stale.
-- Added a delegate-based updater download service that reports live progress into the update dialog.
-- Improved updater install flow to stay user-driven/manual after verification, with Finder handoff instead of in-place app replacement.
-- Improved editor appearance switching so base text colors are enforced immediately on light/dark mode changes across macOS and iOS.
-- Fixed light-mode editor base text color to consistently use dark text across themes.
-
 Full release history: [`CHANGELOG.md`](CHANGELOG.md)
 
 ## Known Limitations
@@ -163,12 +162,12 @@ Full release history: [`CHANGELOG.md`](CHANGELOG.md)
 
 ## Release Integrity
 
-- Tag: `v0.4.18`
+- Tag: `v0.4.19`
 - Tagged commit: `TBD`
 - Verify local tag target:
 
 ```bash
-git rev-parse --verify v0.4.18
+git rev-parse --verify v0.4.19
 ```
 
 - Verify downloaded artifact checksum locally: