Numbers need lines above and below #121
Description
Digits have lines above and below. Modern practice tends to use discreet lines associated with each characters, however older texts used a single line across the whole set of adjacent digits. See examples in the layout requirements document. This difference is likely due to technology constraints. Presumably, a continuous line could be applied using OpenType functionality, but there may be a question about whether a control should allow to switch between one style and the other.
Try the test page.
Initial results indicate that a single line is produced by Noto Sans Ethiopic and Noto Serif Ethiopic, but not by Kefa or Abyssinica SIL fonts.
There is a question as to whether this should be managed by font choice, or whether a switch should be available to users, eg. in CSS, that allows the desired approach to be applied.
In addition to the question just mentioned, a decision needs to be agreed regarding the impact of this feature for the user. For now, this is marked as basic.