MarkdownTextBlock doesn't support '***' for bold+italic

[michael-hawker]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[x] Bug report  <!-- Please search GitHub for a similar issue or PR before submitting -->
[ ] Feature request <!-- Please file a UserVoice request and include the link below https://wpdev.uservoice.com/forums/110705-universal-windows-platform/category/193402-uwp-community-toolkit -->
[ ] Sample app request
[ ] Documentation issue or request
[ ] Question of Support request => Please do not submit support request here, instead see https://github.com/Microsoft/UWPCommunityToolkit/blob/master/contributing.md#question

Current behavior

If you use *** to mark something as bold & italic, it doesn't render as expected:

Expected behavior

Expect rendering:

This is called out in the CommonMark Spec as an acceptable format.

Minimal reproduction of the problem with instructions

1. Open Sample App
2. Open MarkdownTextBlock sample
3. Add ***bold & italic text*** to textbox.

Not sure if this may be fixed by #1650 @WilliamABradley?

Environment

Nuget Package(s): 

Package Version(s): 

Windows 10 Build Number:
- [ ] Anniversary Update (14393) 
- [ ] Creators Update (15063)
- [x] Fall Creators Update (16299)
- [ ] Insider Build (xxxxx)

App min and target version:
- [ ] Anniversary Update (14393) 
- [ ] Creators Update (15063)
- [x] Fall Creators Update (16299)
- [ ] Insider Build (xxxxx)

Device form factor:
- [x] Desktop
- [ ] Mobile
- [ ] Xbox
- [ ] Surface Hub
- [ ] IoT

Visual Studio 
- [ ] 2017 15.3
- [x] 2017 15.4

[WilliamABradley]

I did tweak this some more with #1650, what I have noticed is that while this works:

***Note:*** Warning note

Separating the ending asterisks doesn't:

***Note:** Warning note*

[avknaidu]

@michael-hawker Simultaneous bold and italic is already implemented in #1710 .

Scenario that @WilliamABradley pointed out is not working.

[nmetulev]

I removed this from 2.2 but if one of you nice folks thinks they can add support for the scenario you mentioned in the next week, feel free to assign yourself :)

[Vijay-Nirmal]

Can close this issue

[WilliamABradley]

There is still an issue if the closing asterisks are separated, e.g. ***Hello** With italics*.

Should produce: Hello With italics.

[Vijay-Nirmal]

Ah, I forgot about it. Fun fact: docs.microsoft.com doesn't support it 😄

[gbarcho]

@nmetulev can we close the issue?

[Kyaa-dost]

@WilliamABradley the issue still seems to exist. Do you want to take this on or provide insight?