Variant and regional pronunciations and unknown sounds

When I look at variant pronunciations, sometimes I see things I'm not familiar with. For example looking up 妹 gives "bēr" on the MOE dictionary, and "bō̤" on FHL dictionary. I'm not familiar with "r" and "o̤" (two dots below).

Can someone provide a link with explanations or examples of those specific sounds, or a more comprehensive pronunciation guide of all the things that, I assume, stray from the mixed Taiwanese standard and get closer to the Choan and Chiang end of the spectrum?

The table before "Initials".


But I say you should ignore those and focus on the prestigious dialect.


Turns out both er and o̤ represent the same sound /ə/, just written in TL and POJ. I'm not really trying to "learn" this, I just wanted to unconfuse myself. To-siā--lí!`


詳細答案參考cia, 無標題文件
另外愛補充, 有時解特別用/or/來表達台南腔 or /好/
夭擱有o̤ 值潮州話POJ是 開嘴o