If you select some text and make it bold, and your selection contains an inline template, that template will disappear in the editor, and will be replaced with two snowmen (☃☃) once you move the cursor (and in the wikitext diff, regardless of whether you move the cursor).
Real life example in production:
1. Edit [[https://en.wikipedia.org/wiki/Vancouver|en:Vancouver]] in VisualEditor
2. Select the phrase "a resort community 125 km (78 mi) north of the city"
3. Make it bold. The text "125 km (78 mi)" disappears, and you see "**a resort community north of the city**"
4. Move the cursor. Two snowmen appear where the text "125 km (78 mi)" had been. You now see "**a resort community ☃☃ north of the city**"
5. Click "Publish changes", then "Review your changes". In the wikitext diff, you'll see that `a resort community {{convert|125|km|abbr=on}} north of the city` is changed to `'''a resort community ☃☃ north of the city'''`. This happens regardless of whether or not you do step 4.
{F32379915}
{F32379918}
{F32379922}
{F32379920}