From 699b8a5329e6c19a2fc85c859009e746e95e2067 Mon Sep 17 00:00:00 2001
From: Oliver Kopp <kopp.dev@gmail.com>
Date: Mon, 6 Jul 2026 23:12:21 +0200
Subject: [PATCH] Fix consecutive <br> collapsing into a single line break

RichTextRenderer's Inline.LineBreak case called startParagraph(0),
which only emits model.nl() when the current paragraph is "occupied".
A single <br> correctly closes the preceding text into its own
paragraph, but a second consecutive <br> (e.g. citation styles using
<br><br> for a blank line) found the paragraph already unoccupied and
silently produced nothing, collapsing the blank line.

Mark the paragraph occupied after emitting the break, mirroring the
existing empty-line handling for preserved "\n\n" in appendRun.
---
 .../org/jabref/htmltonode/rich/RichTextRenderer.java   | 10 ++++++++--
 .../org/jabref/htmltonode/RichTextRendererTest.java    | 10 ++++++++++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/src/main/java/org/jabref/htmltonode/rich/RichTextRenderer.java b/src/main/java/org/jabref/htmltonode/rich/RichTextRenderer.java
index 7714254..08cb91b 100644
--- a/src/main/java/org/jabref/htmltonode/rich/RichTextRenderer.java
+++ b/src/main/java/org/jabref/htmltonode/rich/RichTextRenderer.java
@@ -166,8 +166,14 @@ private void paragraph(List<Inline> inlines, double scale, int minWeight, double
                     }
                     appendRun(text, effective);
                 }
-                case Inline.LineBreak ignored ->
-                        startParagraph(0);
+                case Inline.LineBreak ignored -> {
+                    // A break renders as a blank line even with no content of its own, so a second
+                    // consecutive break (e.g. `<br><br>`) still triggers a fresh model.nl() in the next
+                    // startParagraph() call instead of being swallowed by separateParagraph()'s
+                    // occupied-check (mirrors the empty-line handling for preserved "\n\n" in appendRun).
+                    startParagraph(0);
+                    paragraphOccupied = true;
+                }
                 case Inline.Image image -> {
                     if (RenderSupport.createImageView(image, options, baseSize) != null) {
                         model.addNodeSegment(() -> RenderSupport.createImageView(image, options, baseSize));
diff --git a/src/test/java/org/jabref/htmltonode/RichTextRendererTest.java b/src/test/java/org/jabref/htmltonode/RichTextRendererTest.java
index 8f31bc7..8cc70a9 100644
--- a/src/test/java/org/jabref/htmltonode/RichTextRendererTest.java
+++ b/src/test/java/org/jabref/htmltonode/RichTextRendererTest.java
@@ -81,6 +81,16 @@ void lineBreaksSplitParagraphs() {
         assertEquals("b", model.getPlainText(1));
     }
 
+    @Test
+    void consecutiveLineBreaksKeepTheBlankLineBetweenThem() {
+        StyledTextModel model = model("a<br><br>b");
+
+        assertEquals(3, model.size());
+        assertEquals("a", model.getPlainText(0));
+        assertEquals("", model.getPlainText(1));
+        assertEquals("b", model.getPlainText(2));
+    }
+
     @Test
     void preservedNewlinesInPreSplitParagraphs() {
         StyledTextModel model = model("<pre>x = 1\ny = 2</pre>");