What does Buddhism teach or say about Tolerance and accepting differences in general?

Buddhism teaches nature creates differences or diversity. For example:

Again, the Tathagata (Buddha) understands as it actually is the world with its many & different elements. That too is a Tathagata's power...

Again, the Tathagata understands as it actually is how beings have different inclinations. That too is a Tathagata's power...

Again, the Tathagata understands as it actually is the disposition of the faculties of other beings, other persons. That too is a Tathagata's power...

MN 12

Therefore, Buddhism accepts there are differences or diversity in nature and, as a result, extends tolerance, non-hatred & non-violence towards diversity. For example:

Whatever living beings there may be; Whether they are weak or strong, omitting none, The great or the mighty, medium, short or small, The seen and the unseen, Those living near and far away, Those born and to-be-born — May all beings be at ease!

Let none deceive another, Or despise any being in any state. Let none through anger or ill-will Wish harm upon another. Even as a mother protects with her life Her child, her only child, So with a boundless heart Should one cherish all living beings;

Karaniya Metta Sutta

However, just because Buddhism extends tolerance, non-hatred & non-violence towards difference & diversity, this does not mean Buddhism endorses, promotes or recommends all things because Buddhism only endorses, promotes or recommends a moral or non-harming way of life.

For example, Buddhism tolerates murder, theft, rape, sexual promiscuity, dishonesty, drug addiction, usury, gambling, businesses that trade in weapons, slavery, prostitution, intoxicants, etc, however Buddhism does not endorse, promote or recommend these things.

This distinction is shown in the following text about 'tolerating', 'avoiding' & 'destroying' and in Buddhist teachings about 'right' & 'wrong':

[4] And what are the fermentations to be abandoned by tolerating? There is the case where a monk, reflecting appropriately, endures. He tolerates cold, heat, hunger, & thirst; the touch of flies, mosquitoes, wind, sun, & reptiles; ill-spoken, unwelcome words & bodily feelings that, when they arise, are painful, racking, sharp, piercing, disagreeable, displeasing & menacing to life.

[5] And what are the fermentations to be abandoned by avoiding? There is the case where a monk, reflecting appropriately, avoids a wild elephant, a wild horse, a wild bull, a wild dog, a snake, a stump, a bramble patch, a chasm, a cliff, a cesspool, an open sewer. Reflecting appropriately, he avoids sitting in the sorts of unsuitable seats, wandering to the sorts of unsuitable habitats, and associating with the sorts of bad friends that would make his knowledgeable friends in the holy life suspect him of evil conduct.

And what are the fermentations to be abandoned by destroying? There is the case where a monk, reflecting appropriately, does not tolerate an arisen thought of sensuality. He abandons it, dispels it & wipes it out of existence....Reflecting appropriately, he does not tolerate an arisen thought of ill will...Reflecting appropriately, he does not tolerate an arisen thought of cruelty...Reflecting appropriately, he does not tolerate arisen evil, unskillful mental qualities. He abandons them, dispels them, & wipes them out of existence.

MN 2

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In one of right view, wrong view is abolished. The many evil, unskillful qualities that come into play with wrong view as their condition are also abolished, while the many skillful qualities that have right view as their condition go to the culmination of their development. In one of right resolve, wrong resolve is abolished... In one of right speech, wrong speech is abolished... In one of right action, wrong action is abolished... In one of right livelihood, wrong livelihood is abolished... In one of right effort, wrong effort is abolished... In one of right mindfulness, wrong mindfulness is abolished... In one of right concentration, wrong concentration is abolished... In one of right knowledge, wrong knowledge is abolished... In one of right release, wrong release is abolished. The many evil, unskillful qualities that come into play with wrong release as their condition are also abolished, while the many skillful qualities that have right release as their condition go to the culmination of their development. Thus, monks, there are twenty factors siding with skillfulness, and twenty with unskillfulness.

MN 117

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1. Mind precedes all mental states. Mind is their chief; they are all mind-wrought. If with an impure mind a person speaks or acts suffering follows him like the wheel that follows the foot of the ox.

2. Mind precedes all mental states. Mind is their chief; they are all mind-wrought. If with a pure mind a person speaks or acts happiness follows him like his never-departing shadow.

Dhammapada