Add info about regex modifiers (#5200)

ui/v2.5/src/docs/en/Manual/Browsing.md

@@ -25,7 +25,7 @@ Keyword matching uses the following rules:
 * surrounding a phrase in quotes (`"`) matches on that exact phrase. For example, `"foo bar"` matches scenes with `foo bar` in the title. Quotes may also be used to escape the keywords and symbols. For example, `foo "-bar"` will match scenes with `foo` and `-bar`.
 * quoted phrases may be used with the or and not operators. For example, `"foo bar" or baz -"xyz zyx"` will match scenes with `foo bar` *or* `baz`, and exclude those with `xyz zyx`.
 * `or` keywords or symbols at the start or end of a line will be treated literally. That is, `or foo` will match scenes with `or` and `foo`.
-* all matching is case-insensitive
+* all keyword matching is case-insensitive
 
 ### Filters
 
@@ -33,6 +33,10 @@ Filters can be accessed by clicking the filter button on the right side of the q
 
 Note that only one filter criterion per criterion type may be assigned.
 
+#### Regex modifiers
+
+Some filters have regex modifier as an option. Regex modifiers are always case-sensitive.
+
 ### Sorting and page size
 
 The current sorting field is shown next to the query text field, indicating the current sort field and order. The page size dropdown allows selecting from a standard set of objects per page, and allows setting a custom page size.
@@ -43,4 +47,4 @@ Saved filters can be accessed with the bookmark button on the left of the query
 
 ### Default filter
 
-The default filter for the top-level pages may be set to the current filter by clicking the `Set as default` button in the saved filter menu.
+The default filter for the top-level pages may be set to the current filter by clicking the `Set as default` button in the saved filter menu.