If we assume most users will have done the ASCII art trickery inside a code block, with things like |-----+----+----|
and variants, the following SEDE query will find your posts that have any of the following patterns in their body inside a code block:
Here is the query source:
declare @sql nvarchar(max)
create table #result (site sysname
, hostname sysname
, id integer
, title nvarchar(250)
, body nvarchar(max)
)
select @sql = N'insert into #result' + STRING_AGG(concat(N'
select ''', name ,N''' as site
, ''',hostname ,N'''
, p.id
, q.title
, p.body
from ', quotename(name), N'.dbo.users u
inner join ', quotename(name), N'.dbo.posts p on
p.owneruserid = u.id
inner join ', quotename(name), N'.dbo.posts q on
q.id = coalesce(p.parentid, p.id)
where accountid = ##accountid##
'),N'
union all')
from (select convert(nvarchar(max),name) name
-- , convert(nvarchar(max),sitename) sitename
-- , meta
-- , domain
, concat(
-- based on an idea from Glorfindel
-- https://meta.stackexchange.com/a/321181
(case sitename
WHEN 'Audio' THEN 'video'
WHEN 'Beer' THEN 'alcohol'
WHEN 'CogSci' THEN 'psychology'
WHEN 'Garage' THEN 'mechanics'
WHEN 'Health' THEN 'medicalsciences'
WHEN 'Moderators' THEN 'communitybuilding'
WHEN 'Photography' THEN 'photo'
WHEN 'Programmers' THEN 'softwareengineering'
WHEN 'Vegetarian' THEN 'vegetarianism'
WHEN 'Writers' THEN 'writing'
WHEN 'Br' THEN 'pt'
WHEN 'Mathoverflow' THEN concat((meta+'.'), sitename)
ELSE case when sitename = domain then null else sitename end
end +'.')
, (case
when sitename <> 'mathoverflow' then (meta+'.')
else null
end)
, (case
when sitename <> 'mathoverflow' then concat((domain + '.'), 'com')
else 'net'
end)
) hostname
from (
select name
, case parsename(name,1)
when 'Meta' then parsename(name,2)
else parsename(name,1)
end [sitename]
, case parsename(name,1)
when 'Meta' then 'meta'
else null
end [meta]
, coalesce(parsename(name,3), parsename(name,2)) [domain]
from sys.databases
where database_id > 5
and (name not like '%.Meta' or name = 'StackExchange.Meta')
) dbs
) dbsall
exec (@sql)
select concat(
'https://'
, hostname
, '/q/'
, id
, '|'
, title) [Post]
, value
from #result
cross apply string_split('----,|--,--+--,--|--',',') line -- patterns comma separted
where body like concat('%<code>%', line.value, '%</code>%')
The query needs your accountid that is found in the url of your network profile. The detected ascii art patterns are near the end, in the string_split function.
When run today this is the result for user einpoklum:

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