Without installing any extension:
Open console and type:
document.getElementsByTagName('table')
If there is more than one, use the index for the desired table.
In my case I want the first table so I use 0 as the index:
document.getElementsByTagName('table')[0]
Define column you want (first column is 0):
column = 0
And this is the final code:
Array.from(document.getElementsByTagName('table')[0].getElementsByTagName('tr'))
.map(tr => tr.getElementsByTagName('td'))
.filter(td => td.length > 0)
.map(td => td[column].innerHTML)
Now you have the output, which you can copy from the console, e.g. ["Item 1", "Item 2", "Item 3"]