Activity Diagram: Why is a letter in a circle rendered in SVG as a path?

Question

See this example:

(by the way,  how do I embed a live example like I see in other questions?)

@startuml
<style>
circle{ BackgroundColor Yellow }
.connector{ BackgroundColor Pink; Padding 2 5 }
</style>
title Test of SVG rendering of Circle
:A;<<connector>>
(B)
(C)
@enduml

When the above is rendered to SVG, the B and C connectors are rendered as follows:

<ellipse cx="146" cy="96.2656" fill="#FFFF00" rx="10" ry="10" style="stroke:#181818;stroke-width:0.5;"/>

<path d="M144.8594,96.5938 L144.8594,99.7969 L146.7656,99.7969 Q147.7188,99.7969 148.1719,99.4063 Q148.6406,99 148.6406,98.1875 Q148.6406,97.3594 148.1719,96.9844 Q147.7188,96.5938 146.7656,96.5938 L144.8594,96.5938 Z M144.8594,92.9844 L144.8594,95.625 L146.6094,95.625 Q147.4844,95.625 147.9063,95.2969 Q148.3281,94.9688 148.3281,94.3125 Q148.3281,93.6406 147.9063,93.3125 Q147.4844,92.9844 146.6094,92.9844 L144.8594,92.9844 Z M143.6719,92.0156 L146.7031,92.0156 Q148.0625,92.0156 148.7813,92.5781 Q149.5156,93.1406 149.5156,94.1719 Q149.5156,94.9844 149.1406,95.4688 Q148.7656,95.9375 148.0469,96.0469 Q148.9219,96.2344 149.4063,96.8281 Q149.8906,97.4219 149.8906,98.3125 Q149.8906,99.4844 149.0938,100.125 Q148.2969,100.7656 146.8125,100.7656 L143.6719,100.7656 L143.6719,92.0156 Z " fill="#000000"/>

<ellipse cx="146" cy="136.2656" fill="#FFFF00" rx="10" ry="10" style="stroke:#181818;stroke-width:0.5;"/>

<path d="M148.7344,132.6875 L148.7344,133.9375 Q148.125,133.375 147.4531,133.1094 Q146.7813,132.8281 146.0156,132.8281 Q144.5156,132.8281 143.7188,133.75 Q142.9219,134.6719 142.9219,136.4063 Q142.9219,138.125 143.7188,139.0469 Q144.5156,139.9688 146.0156,139.9688 Q146.7813,139.9688 147.4531,139.6875 Q148.125,139.4063 148.7344,138.8594 L148.7344,140.0938 Q148.1094,140.5156 147.4063,140.7344 Q146.7188,140.9375 145.9531,140.9375 Q143.9531,140.9375 142.8125,139.7188 Q141.6719,138.5 141.6719,136.4063 Q141.6719,134.2969 142.8125,133.0781 Q143.9531,131.8594 145.9531,131.8594 Q146.7344,131.8594 147.4219,132.0781 Q148.125,132.2813 148.7344,132.6875 Z " fill="#000000"/>

​The circle is an ellipse, but the single letter inside is rendered as a path. Why is that?