Repository graph should have visual difference between branches and tags
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This is essentially the same issue as #325877 and #1539. Both issues were closed without resolution.
**Problem:** Repository graphs currently display branches and tags with the same style (white text on dark gray "bubble") and this makes it difficult to distinguish them at a glance.
**Suggestion:** It would be preferable to have a different visual style for branches and tags. For example, branches could retain the dark gray bubble, while tag bubbles could adopt the colour of the graph nodes; something like the image below. Of course, other solutions exist.
Thanks.
{width=166 height=388}
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