Stacked annotations on same span not correctly represented for two annotators in CSV diff export

[lfcc1]

Describe the bug When two annotators create stacked annotations (i.e., multiple tags) over the same text span, the CSV file generated to compare their annotations does not correctly represent the stacked annotations of the second annotator. Instead, it only shows the annotations from the first annotator, and marks the corresponding entry for the second annotator as <no annotation>, even though the same span was annotated with stacked annotations by both.

To Reproduce Steps to reproduce the behavior: 1-Have two annotators annotate the same document. 2-Both annotators create stacked annotations (e.g., two labels on the same span). 3-Export the annotation differences to CSV. 4-Open the CSV and locate a line where both annotators stacked annotations on the same span. 5-Notice that only the first annotator’s stacked annotations are shown; the second appears as <no annotation>.

Expected behavior The CSV should show the stacked annotations for both annotators if they exist. The entry for the second annotator should not be when valid annotations were made.

Screenshots First annotator:

Second annotator:

CSV line: 1364-1455 [O Hamas e os seus apoiantes encorajam a erradicação do povo judeu nas redes sociais há anos],STACKED,"Claim, Claim span",<no annotation>

Please complete the following information:

• Version and build ID: 35.2 (2025-02-04 07:13:24, build 18f5fdcd)
• OS: Linux
• Browser: edge