Add special characters for search - Comprehensive List?

Further testing for period, forward slash, and en dash characters (all character that returned no results in standalone search - see above).

• Changed . instance to I.O
• Changed / instance to I/O
• Changed - instance to 4444-0122

In the output:

• A string search value of "I.O" (included the quotes), returned the desired/targeted test topic.
• Likewise, a string search value of "I/O" returned the desired/targeted test topic.
• And as expected at this point, a string search value of "4444-0122" returned the desired/targed test topic.
• Note that for all three of these tests, the entire search value was highlighted when I opened the target from the results - that includes the special character and text after it.
• As an additional test, I performed searches on unsupported special characters with only the character enclosed in quotes, for example, "/"; the output did not return any results.

No response from Adobe yet, but here are the results from my personal testing.

• This was performed against a single (i.e., not merged) Frameless output in 2020.5.
• Not sure if the results would be the same for Responsive HTML5 and merged.
• I listed all of these special characters in the "Add special characters for search" field.
• I listed all of these special characters in the same topic (each inside its own dedicated open and close paragraph tag)
• I applied H1 style to each character (to move the topic to the top of the results in case there were multiples)
• I searched ONLY on the special character.
• I have did NOT test string search (enclosed by quotes); that'll be my next test. 

no = No Results Found (the message returned)
yes = one or more results returned

~  no
!  no

@  yes
#  yes
$  yes
%  yes
^  yes
&  yes
*  no
(  no
)  no
_  yes
+  no
`  yes
1  yes
2  yes
3  yes
4  yes
5  yes
6  yes
7  yes
8  yes
9  yes
0  yes
-  no
=  yes
{  no
}  no
|  no
[  no
]  no
\  no
:  no
"  no
;  no
'  no
<  no
>  no
?  no
,  no
.  no
/  no

Thank you for the recommendation. I emailed Support via their guidelines. I'll update this post - hopefully with the requested info - with their response.

I am not aware of any such list so I think this will be one for Support. See https://helpx.adobe.com/contact/enterprise-support.other.html#robohelp for your Adobe Support options. The email link tcssup@adobe.com is recommended as it reaches a team dedicated to Technical Communication Suite products including RoboHelp. 

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