Book: Add FAQ section (#203)

* Book: Add FAQ section

* Add note about list marker workaround

* Reflow text to not exceed 80 columns

Author: rmburg

book/src/SUMMARY.md

@@ -20,6 +20,7 @@
   - [Next heading](./toolbox/next-heading.md)
   - [Big](./toolbox/big.md)
   - [Full width](./toolbox/full-width.md)
+- [FAQ](./faq/faq.md)
 - [External tools](./external/external.md)
   - [pdfpc](./external/pdfpc.md)
 - [Changelog](./changelog.md)

book/src/dynamic/obo-lbl.md

@@ -56,3 +56,8 @@ A more complex example involving enums and term lists:
 
 Note that the list markers and enum numbers are not hidden.
 You can truly consider this a bug or a feature...
+
+This is due to a [bug](https://github.com/typst/typst/issues/619) in typst.
+See the
+[FAQ](../faq/faq.md#is-it-possible-to-also-hide-the-markers-of-hidden-list-items)
+for a workaround.

book/src/faq/faq.md

@@ -0,0 +1,32 @@
+# Frequently Asked Questions
+
+## Is it possible to also hide the markers of hidden list items?
+
+Yes. You can use the following show rules:
+
+```typ
+#let no-par-spacing(it) = (
+  context {
+    set par(spacing: par.leading)
+    it
+  }
+)
+
+#show list: no-par-spacing
+#show enum: no-par-spacing
+
+#show hide: it => {
+  show list.item: list
+  show enum.item: enum
+
+  it
+}
+```
+This works by splitting up the list into multiple lists,
+each with one list item.
+This change hides the list marker properly,
+but also increases the spacing between individual list items
+(as the items are now individual lists).
+The first two show rules in the snippet above fix this by reducing
+the spacing between lists to be the same as the
+spacing between list items within one list.