It just caught my eyes that in the Artscroll siddur I use in the synagogue writes Bemidbar 15:39 the following way:
וְהָיָ֣ה לָכֶם֮ לְצִיצִת֒ וּרְאִיתֶ֣ם אֹת֗וֹ וּזְכַרְתֶּם֙ אֶת־כָּל־מִצְוֺ֣ת יְהוָ֔ה וַֽעֲשִׂיתֶ֖ם אֹתָ֑ם וְלֹֽא־תָת֜וּרוּ אַֽחֲרֵ֤י לְבַבְכֶם֙ וְאַֽחֲרֵ֣י עֵֽינֵיכֶ֔ם אֲשֶׁר־אַתֶּ֥ם זֹנִ֖ים אַֽחֲרֵיהֶֽם׃
And it shall be unto you for a fringe, that ye may look upon it, and remember all the commandments of Hashem, and do them; and that ye go not about after your own heart and your own eyes, after which ye use to go astray.
Almost in all other siddurim and chumashim I know there is a kadma on the word ולא. I found it this way in R' Heidenheim's siddur, but R' Emden (p. 253) seems to omit the kadma as well. Mechon Mamre, Mikraot Gedolot haKeter, R' Yellin's chumash and the Leningrad Codex (seemingly) support the version without kadma, yet Koren and my older Artscroll siddur both write it with kadma. Are there any rabbinical sources discussing this issue?