Being Chinese, I thought this was a rather interesting question. I personally have not heard of such a taboo, but since there are regional variants on bad Chinese gifts, this might vary with area, and is certainly not authoritative.
Due to this, unless some academic publishes a research paper on the topic of Chinese taboos with properly cited information, it would be nearly impossible to obtain non-subjective sources.
A Baidu search on the term "送蜡烛 忌讳" (gifting a candle taboo) shows a number of differing interpretations, slightly tending towards negative, with no clear consensus on whether it is or is not a good idea. Many of the questions seem to be dealing with candles being given as gifts between lovers or as birthday presents, so it seems that a taboo, if it exists, is not especially widespread.
On the positive connotations side:
Candles are used for newly-wed couples, as evidenced by the Chinese term "洞房花烛". This could be the reasoning behind why so many people were asking about it in the context of lover relationships.
On the negative connotations side:
Candles are used as offerings for the dead during Hungry Ghost Festival. Both red and white candles are used, where white candles are used during the initial funeral, while red candles are used on subsequent years.
This was used as one of the reasons against giving a gift of candles in this link.
Candles are for use at funerals and death rituals, and are unsuitable as gifts.
The same source also quotes that dolls are an unsuitable gift (giving a rationale which seems very close to voodoo)
The term "吹灯拔蜡" also has negative connotations, in the sense similar to the "umbrella" example that you linked in your original post.
Of course, since I did not know about any of these taboos prior to this, combined with the fact that you are not Chinese, it would almost certainly be accepted without poor connotations. This would be further enhanced as a gift since Christmas candles are a thing in your home country.