In Myth, Did 🧝Elves Flee to Gondolin After Defeat?

[Turin_Turambar]

According to what I read somewhere, after the elves were heavily defeated in Dagor Bragollach, some Noldor and Sindar elves who escaped from the war came to the gondolin and settled in it. Even among these elves were Glorfindel and Ecthelion. Is this article true? Is there any truth to it?

 

[Elthir]

Since Ecthelion is involved, you can once again consult my post Everything Ecthelion (almost), found in the atatched thread. Wow. I really can't spell attached.

https://thetolkien.forum/threads/is-it-certain-that-ecthelion-was-born-in-valinor.29606/#post-542318

Even with respect to the constructed Silmarillion references, I dared to write:

Of the four page references the only possibly “notable” differences from HME appear to be:

Of The Fifth Battle I can’t yet find a Tolkien-written source for naming the captains Ecthelion and Glorfindel with respect to guarding the flanks of Turgon’s retreat toward the Pass of Sirion.

Editorial addition maybe?

And I still haven't found a (JRR) Tolkien-written source.

Edit: found it -- it's in The Children of Húrin version!