I have ẞ (Germandbls), both, uc and sc.
When I check sc fea in Glyphs everything is ok; Straße became S/t.sc/r.sc/a.sc/germandbls.sc/e.sc
but when I change lc to sc in InDesign it change it to Strasse?
And when changing Straße to all caps it became STRASSE
Why?
Indesign does overwrite the ß for small caps and All Caps. You can’t do anything with features to change that.
It sounds like a really bad joke.
So the only way to get proper germandbls is via Glyphs pallete in InDesign.
Way to go Adobe.
http://www.glyphsapp.com/tutorials/localize-your-font-german-capital-sharp-s
I recommend that a small cap germandbls.sc looks like to small cap s anyway (s.smcp+s.smcp=germandbls.smcp). But the Germandbls.c2sc should look like small cap ẞ. And you can type ẞ in InDesign, too.
Thnx Rainer, half a problem is solved with .calt.
I don’t have a two sets of Small Caps, just a .sc.
If I type STRAẞE choosing all smcp in OT fea dropdown menu it change ẞ to ẞ.sc. Ok.
But klicking SC Icon Straße becames Strasse, again.
You may know that the idea of adding a cap eszett is disliked by many German type designers and typogaphers.
So, in a way I think many type designers and typogaphers are happy about Adobe’s practice to convert to ss since that is what they consider the right practice.
If Adobe introduces support for cap eszett in all caps and small caps then they need to provide a user option to decide which practice to apply, otherwise many InDesign users will be upset.
Officially, the uppercase Germandbls is merely a ß that fits to uppercase letters (cap height instead of ascender, color, etc.). But there has been a century-old discussion about introducing it to the official orthography as well.
If you have a weekend to spare, you will find plenty of articles about it all over the web. 
@ Tim, I see, it seems I saw just a one part opinions.
@ Rainer, thank you again, I’ll wait for you guys to have a strong and signed agreement on this topic 
Does anyone know of fonts that have a small caps version of the Germandbls? I’m interested in particular in a sans serif similar to Scala Sans. Thanks.
Perhaps this is the wrong forum for font ID questions. Typophile is a better place for this.
Following the Glyphs suggestions for Germandbls (with germandbls.calt => Localize your font: German capital sharp S | Glyphs) you get this case, where it reverts back when you have a break in the word.!
Would it make sense, to avoid that case to also add a germandbls.case ?
True. You could add it to the case code, which would trigger the cap sharp S whenever the user chooses all cap text in InDesign. It would not catch the case where a user just types with the Shift key held down.
A different solution to which the Typejockeys pointed me is to change the contextual substitution to react to a cap after the sharp s, rather than the sharp s between two caps. This would catch your case as well, no matter how they user produced the all-cap text.
Only difference – case also reacts with “Adobe Einzeilen/Absatzsetzer” (Standard in german Indesign) while calt only reacts works with the “Globaler Einzeilen/Absatzsetzer”. (Or maybe I am missing something here) Either way, is there any reason to not just do all three things? A case version, a calt version, and the code you suggest plus the Typejockey solution?
calt should work in both composers. (Just tried again, and the sharp S replacement works in both in CC 2019.) I believe certain lookup types don’t work in the legacy composer, like chaining contextual, but this is not the case here. ccmp is ignored in the legacy composer.
Ah okay, thanks! Then this is fixed in newer versions – in old CS Indesign versions, this was still an issue with the standard setting of Adobe paragraph composer:
But is there a reason you can think of, why you would advice against a calt and case version?
if you let Indesign do the case conversion, it will do the ß > SS automatically and before the OpenType layout. If you type the uppercase yourself, it should work.
Yes, this is not the effect of calt not working, but a replacement by the layout engine (in the legacy composer) when you press the All Caps button (Cmd-Shift-K) in InDesign.
Thanks for your help, both of you!
I have another follow up question about the .case version.
There is a case (and I know this might be very very rare…) where a germandbls.case (that is a component glyph of Germandbls) would be good is: «Aß sie etwas?» in All Caps. With the calt feature, this cannot substitute (otherwise we make «Aẞ sie etwas?» happen).
Is your advice to disregard this case, use germandbls.case, or do you have another solution for this?
Actually this should be a job for the layout engine. But it will still take time until the new orthography has trickled into all software.
In the case of Adobe perhaps even years, because I assume they are reluctant to invest into updating all their TypeKit fonts. And they would not want to add a feature that their own fonts do not support.
