How to un-LingQ words?

Yesterday I imported a private text and began to work through the blue words.
Later I decided that I should stick to the lessons I already have and not yet bother with words that won’t turn up anywhere else (if I just left them LingQed they would keep turning up in the reviews and I don’t want that).
This morning I went to the vocabulary page, selected the LingQs I created yesterday and deleted them. A few using the red x on the right, a whole batch using mass changes.
I opened the lesson and expected to see the words in blue again. But they are white, same as known words. I deleted the browser cache but no change.

Help! I will need those later so they should revert back to being blue.

You cannot convert them to blue. But you can create LingQs for them and make them yellow.

That’s right. As Vera said, you are only able to highlight words again and create LingQs of them.

Then I would like to place an enhancement request. It really should be possible to return yellow words to blue. I’m sure I’m not the only one who works on the wrong lesson.

There was no reason to delete them. They could have been useful for other lessons as well. The LingQs are not connected to the lesson you are working on only. The LingQs works for all lessons. You could have deleted the lesson without deleting the LingQs.

For me there were several reasons even if there isn’t one for you or anyone else, e.g. the fact that I don’t want to review LingQs not connected to current or past lessons.
Sorry to have bothered you.

No, no. I’m not bothered. I just wanted to explain how it works. Your request came up before but it was always refused bei the LingQ staff.