test

The number of conjuncts supported fonts varies, so set the font to a specific value.
Identify the clusters that are presented by the font using a visible virama – these are the ones we are testing. (You can highlight some or all of these by clicking on them.)
From the pulldown labelled "Run a test" choose "First-letter".
Check the results.
Test passes if only the first consonant+virama is highlighted in clusters that had a visible virama in the default display.

• Gecko: Firefox/87.0 Mac OS X 11_2_3 ✓
• Blink: Chrome/89.0.4389.90 Mac OS X 11_2_3 ✘ The whole cluster is highlighted.
• Webkit: Safari/605.1.15 Mac OS X 11_2_3 ✘ The whole cluster is highlighted.

Note: #69 tests for the other clusters, which form conjuncts.